Nanomaterials

17 pages, 7747 KiB

Open AccessEditor’s ChoiceArticle

Calcium Phosphate Nanoparticles Functionalized with a Cardio-Specific Peptide

by Federica Mancini, Lorenzo Degli Esposti, Alessio Adamiano, Jessica Modica, Daniele Catalucci, Dora Mehn, Otmar Geiss and Michele Iafisco

Nanomaterials 2025, 15(2), 94; https://doi.org/10.3390/nano15020094 - 9 Jan 2025

Viewed by 1027

Abstract

Cardiovascular diseases (CVDs) remain the leading cause of mortality worldwide, highliting the urgent need for new therapeutic strategies. Peptide-based therapies have demonstrated significant potential for treating CVDs; however, their clinical application is hindered by their limited stability in physiological fluids. To overcome this [...] Read more.

Cardiovascular diseases (CVDs) remain the leading cause of mortality worldwide, highliting the urgent need for new therapeutic strategies. Peptide-based therapies have demonstrated significant potential for treating CVDs; however, their clinical application is hindered by their limited stability in physiological fluids. To overcome this challenge, an effective drug delivery system is essential to protect and efficiently transport peptides to their intended targets. This study introduces two distinct strategies for loading a cardio-specific mimetic peptide (MP), previously designed to modulate L-type calcium channel function in cardiomyocytes, onto calcium phosphate nanoparticles (CaP NPs). MP-loaded CaP NPs were prepared by two different wet precipitation syntheses, one of which involved the use of sodium polyacrylate as a templating agent. Characterization of MP-loaded CaP NPs showed that their crystallinity, size, surface charge, and morphology could be tuned by adjusting the synthesis parameters. In vitro tests on cardiac cells confirmed that both types of MP-loaded CaP NPs are biocompatible with HL-1 cardiomyocytes and restored intracellular calcium flux under stressed conditions, highlighting their therapeutic potential. These results pave the way for further optimization of CaP NP formulations and suggest their potential as a viable nanomaterial for CVD treatment. Full article

(This article belongs to the Special Issue Applications of Calcium Phosphate-Based Nanostructured Materials and Coatings: 2nd Edition)

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15 pages, 8790 KiB

Open AccessEditor’s ChoiceArticle

A Graphene/MXene-Modified Flexible Fabric for Infrared Camouflage, Electrothermal, and Electromagnetic Interference Shielding

by Xianguang Hou, Ziyi Zang, Yaxin Meng, Tian Wang, Shuai Gao, Qingman Liu, Lijun Qu and Xiansheng Zhang

Nanomaterials 2025, 15(2), 98; https://doi.org/10.3390/nano15020098 - 9 Jan 2025

Viewed by 1539

Abstract

Although materials with infrared camouflage capabilities are increasingly being produced, few applications exist in clothing fabrics. Here, graphene/MXene-modified fabric with superior infrared camouflage, Joule heating, and electromagnetic shielding capabilities all in one was prepared by simply scraping a graphene slurry onto alkali-treated cotton [...] Read more.

Although materials with infrared camouflage capabilities are increasingly being produced, few applications exist in clothing fabrics. Here, graphene/MXene-modified fabric with superior infrared camouflage, Joule heating, and electromagnetic shielding capabilities all in one was prepared by simply scraping a graphene slurry onto alkali-treated cotton fabrics, followed by spraying MXene. The functionality of the modified fabrics after different treatment times was then tested and analyzed. The results indicate that the mid-infrared emissivity of the modified fabric decreases with an increase in the coating times of graphene and MXene. When the graphene/MXene-modified fabrics are prepared at loads of 5 and 1.2 mg/cm², respectively, the modified fabrics have very low infrared emissivity in the 3–5 and 8–14 μm bands, and the surface temperature can be reduced by 53.1 °C when placed on a heater with a temperature of 100 °C (surface radiation temperature of 95 °C). The modified fabric also demonstrates excellent Joule heating capabilities; at 4 V of power, a temperature of 91.7 °C may be reached in 30 s. In addition, customized materials exhibit strong electromagnetic shielding performance. By simply folding the cloth, the electromagnetic interference shield effect can be increased to 64.3 dB. With their superior infrared camouflage, thermal management, and electromagnetic shielding performance, graphene/MXene-modified fabrics have found extensive use in intelligent wearables and military applications. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

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18 pages, 5127 KiB

Open AccessEditor’s ChoiceArticle

Green Synthesis of Copper Nanoparticles from the Aqueous Extract of Lonicera japonica Thunb and Evaluation of Its Catalytic Property and Cytotoxicity and Antimicrobial Activity

by Weijie Yu, Jingyi Tang, Chunxia Gao, Xuesong Zheng and Peizhi Zhu

Nanomaterials 2025, 15(2), 91; https://doi.org/10.3390/nano15020091 - 9 Jan 2025

Viewed by 1221

Abstract

In this study, copper nanoparticles with an average particle size of 2–4 nm were synthesized using the green extract of Lonicera japonica Thunb. The catalytic activity and dye degradation efficiency of Cu NPs were evaluated using ultraviolet spectroscopy. To confirm that Cu NPs [...] Read more.

In this study, copper nanoparticles with an average particle size of 2–4 nm were synthesized using the green extract of Lonicera japonica Thunb. The catalytic activity and dye degradation efficiency of Cu NPs were evaluated using ultraviolet spectroscopy. To confirm that Cu NPs can continuously remove organic dyes, this study used Cu/Lj-C composite material adsorbed on cotton balls as a simulated bed to study the cyclic catalytic activity of Cu NPs for the reduction of methylene blue by sodium borohydride (NaBH₄). The experiment showed that after multiple cycles, it can also quickly and effectively reduce methylene blue. To evaluate the toxicity of Cu NPs, experiments were conducted using HUVEC and MC3T3-E1 cells. The median lethal doses (LD₅₀) were 37.64 µg/mL and 7.50 µg/mL. The synthesized Cu NPs also exhibited antibacterial efficacy against Aspergillus niger (fungus), Staphylococcus aureus (Gram-positive bacteria), Escherichia coli (Gram-negative bacteria), and Candida albicans (yeast). Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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31 pages, 8883 KiB

Open AccessEditor’s ChoiceReview

Research on Red/Near-Infrared Fluorescent Carbon Dots Based on Different Carbon Sources and Solvents: Fluorescence Mechanism and Biological Applications

by Jun Song, Minghao Kang, Shujian Ji, Shuai Ye and Jiaqing Guo

Nanomaterials 2025, 15(2), 81; https://doi.org/10.3390/nano15020081 - 7 Jan 2025

Cited by 1 | Viewed by 1105

Abstract

Fluorescent carbon dots, especially red/near-infrared-emitting CDs, are becoming increasingly important in the field of biomedicine. This article reviews the synthesis, fluorescence mechanisms, and biological applications of R/NIR-CDs, emphasizing the importance of carbon source and solvent selection in controlling their optical properties. The formation [...] Read more.

Fluorescent carbon dots, especially red/near-infrared-emitting CDs, are becoming increasingly important in the field of biomedicine. This article reviews the synthesis, fluorescence mechanisms, and biological applications of R/NIR-CDs, emphasizing the importance of carbon source and solvent selection in controlling their optical properties. The formation process of CDs is classified, and the fluorescence mechanisms of CDs are summarized, involving carbon core states, surface states, molecular states, and cross-linking enhanced emission effects. This article also highlights the applications of R/NIR-CDs in bioimaging, biosensing, phototherapy, and drug delivery. The final section discusses challenges and prospects. Full article

(This article belongs to the Section Nanophotonics Materials and Devices)

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20 pages, 3114 KiB

Open AccessEditor’s ChoiceArticle

Tin(IV)Porphyrin-Based Porous Coordination Polymers as Efficient Visible Light Photocatalyst for Wastewater Remediation

by Nirmal Kumar Shee and Hee-Joon Kim

Nanomaterials 2025, 15(1), 59; https://doi.org/10.3390/nano15010059 - 2 Jan 2025

Viewed by 1139

Abstract

Two porphyrin-based polymeric frameworks, SnP-BTC and SnP-BTB, as visible light photocatalysts for wastewater remediation were prepared by the solvothermal reaction of trans-dihydroxo-[5,15,10,20-tetrakis(phenyl)porphyrinato]tin(IV) (SnP) with 1,3,5-benzenetricarboxylic acid (H₃BTC) and 1,3,5-tris(4-carboxyphenyl)benzene (H₃BTB), respectively. The strong bond between the carboxylic acid [...] Read more.

Two porphyrin-based polymeric frameworks, SnP-BTC and SnP-BTB, as visible light photocatalysts for wastewater remediation were prepared by the solvothermal reaction of trans-dihydroxo-[5,15,10,20-tetrakis(phenyl)porphyrinato]tin(IV) (SnP) with 1,3,5-benzenetricarboxylic acid (H₃BTC) and 1,3,5-tris(4-carboxyphenyl)benzene (H₃BTB), respectively. The strong bond between the carboxylic acid group of H₃BTC and H₃BTB with the axial hydroxyl moiety of SnP leads to the formation of highly stable polymeric architectures. Incorporating the carboxylic acid group onto the surface of SnP changes the conformational frameworks as well as produces rigid structural transformation that includes permanent porosity, good thermodynamic stability, interesting morphology, and excellent photocatalytic degradation activity against AM dye and TC antibiotic under visible light irradiation. The photocatalytic degradation activities of AM dye were found to be 95% by SnP-BTB and 87% by SnP-BTC within 80 min. Within 60 min of visible light exposure, the photocatalytic degradation activities of TC antibiotic were found to be 70% by SnP-BTB and 60% by SnP-BTC. The enhanced catalytic photodegradation performances of SnP-BTB and SnP-BTC were attributed to the synergistic effect between SnP and carboxylic acid groups. The carboxylic acid connectors strongly resist the separation of SnP from the surface of SnP-BTB and SnP-BTC during the photodegradation experiments. Therefore, the high degradation rate and low catalyst loading make SnP-BTB or SnP-BTC more efficient than other reported catalysts. Thus, the present investigations on the porphyrin-based photocatalysts hold great promise in tackling the treatment of dyeing wastewater. Full article

(This article belongs to the Special Issue Environmental Restoration Materials and Technologies)

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13 pages, 3997 KiB

Open AccessEditor’s ChoiceArticle

Reliable Atom Probe Tomography of Cu Nanoparticles Through Tailored Encapsulation by an Electrodeposited Film

by Aydan Çiçek, Florian Knabl, Maximilian Schiester, Helene Waldl, Lidija D. Rafailović, Michael Tkadletz and Christian Mitterer

Nanomaterials 2025, 15(1), 43; https://doi.org/10.3390/nano15010043 - 30 Dec 2024

Viewed by 897

Abstract

Nanoparticles are essential for energy storage, catalysis, and medical applications, emphasizing their accurate chemical characterization. However, atom probe tomography (APT) of nanoparticles sandwiched at the interface between an encapsulating film and a substrate poses difficulties. Poor adhesion at the film-substrate interface can cause [...] Read more.

Nanoparticles are essential for energy storage, catalysis, and medical applications, emphasizing their accurate chemical characterization. However, atom probe tomography (APT) of nanoparticles sandwiched at the interface between an encapsulating film and a substrate poses difficulties. Poor adhesion at the film-substrate interface can cause specimen fracture during APT, while impurities may introduce additional peaks in the mass spectra. We demonstrate preparing APT specimens with strong adhesion between nanoparticles and film/substrate matrices for successful analysis. Copper nanoparticles were encapsulated at the interface between nickel film and cobalt substrate using electrodeposition. Cobalt and nickel were chosen to match their evaporation fields with copper, minimizing peak overlaps and aiding nanoparticle localization. Copper nanoparticles were deposited via magnetron sputter inert gas condensation with varying deposition times to yield suitable surface coverages, followed by encapsulation with the nickel film. In-plane and cross-plane APT specimens were prepared by femtosecond laser ablation and focused ion beam milling. Longer deposition times resulted in agglomerated nanoparticles as well as pores and voids, causing poor adhesion and specimen failure. In contrast, shorter deposition times provided sufficient surface coverage, ensuring strong adhesion and reducing void formation. This study emphasizes controlled surface coverage for reliable APT analysis, offering insights into nanoparticle chemistry. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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19 pages, 10251 KiB

Open AccessEditor’s ChoiceArticle

Nanosized κ-Carbide and B2 Boosting Strength Without Sacrificing Ductility in a Low-Density Fe-32Mn-11Al Steel

by Changwei He, Yongfeng Shen, Wenying Xue, Zhijian Fan and Yiran Zhou

Nanomaterials 2025, 15(1), 48; https://doi.org/10.3390/nano15010048 - 30 Dec 2024

Cited by 2 | Viewed by 809

Abstract

High-performance lightweight materials are urgently needed because of energy savings and emission reduction. Here, we design a new steel with a low density of 6.41 g/cm³, which is a 20% weight reduction compared to the conventional steel. The mechanical properties and [...] Read more.

High-performance lightweight materials are urgently needed because of energy savings and emission reduction. Here, we design a new steel with a low density of 6.41 g/cm³, which is a 20% weight reduction compared to the conventional steel. The mechanical properties and microstructures of the steels prepared with different routes are systematically explored by utilizing uniaxial tensile testing and transmission electron microscopy. The steel processed by cold rolling and recrystallization annealing at 950 °C for 15 min shows an ultra-high yield strength of 1241 ± 10 MPa, while retaining a good ductility of 38 ± 1%. The high yield strength is mainly related to the synergistic precipitation strengthening introduced by nanoscale B2 and κ′-carbides. It is encouraging to notice that the yield strength increased without scarifying ductility, compared to the ST steel. The key reason is that the high strain hardening rate is activated by combined factors, including the blockage of numerous twins and nanoscale B2 to the dislocation movements, and dynamic slip band refinement. This study is instructive for concurrently enhancing the strength and ductility of austenitic lightweight steels with fully recrystallized grains and dual nano-precipitates. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

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21 pages, 5129 KiB

Open AccessEditor’s ChoiceArticle

Peroxidase (POD) Mimicking Activity of Different Types of Poly(ethyleneimine)-Mediated Prussian Blue Nanoparticles

by Udara Bimendra Gunatilake, Briza Pérez-López, Maria Urpi, Judit Prat-Trunas, Gerard Carrera-Cardona, Gautier Félix, Saad Sene, Mickaël Beaudhuin, Jean-Charles Dupin, Joachim Allouche, Yannick Guari, Joulia Larionova and Eva Baldrich

Nanomaterials 2025, 15(1), 41; https://doi.org/10.3390/nano15010041 - 29 Dec 2024

Viewed by 1151

Abstract

Prussian blue nanoparticles (PBNPs) have been identified as a promising candidate for biomimetic peroxidase (POD)-like activity, specifically due to the metal centres (Fe³⁺/Fe²⁺) of Prussian blue (PB), which have the potential to function as catalytically active centres. The decoration [...] Read more.

Prussian blue nanoparticles (PBNPs) have been identified as a promising candidate for biomimetic peroxidase (POD)-like activity, specifically due to the metal centres (Fe³⁺/Fe²⁺) of Prussian blue (PB), which have the potential to function as catalytically active centres. The decoration of PBNPs with desired functional polymers (such as amino- or carboxylate-based) primarily facilitates the subsequent linkage of biomolecules to the nanoparticles for their use in biosensor applications. Thus, the elucidation of the catalytic POD mimicry of these systems is of significant scientific interest but has not been investigated in depth yet. In this report, we studied a series of poly(ethyleneimine) (PEI)-mediated PBNPs (PB/PEI NPs) prepared using various synthesis protocols. The resulting range of particles with varying size (~19–92 nm) and shape combinations were characterised in order to gain insights into their physicochemical properties. The POD-like nanozyme activity of these nanoparticles was then investigated by utilising a 3,3′,5,5′-tetramethylbenzidine (TMB)/H₂O₂ system, with the catalytic performance of the natural enzyme horseradish peroxidase (HRP) serving as a point of comparison. It was shown that most PB/PEI NPs displayed higher catalytic activity than the PBNPs, with higher activity observed in particles of smaller size, higher Fe content, and higher Fe²⁺/Fe³⁺ ratio. Furthermore, the nanoparticles demonstrated enhanced chemical stability in the presence of acid, sodium azide, or high concentrations of H₂O₂ when compared to HRP, confirming the viability of PB/PEI NPs as a promising nanozymatic material. This study disseminates fundamental knowledge on PB/PEI NPs and their POD-like activities, which will facilitate the selection of an appropriate particle type for future biosensor applications. Full article

(This article belongs to the Special Issue Advanced Porous Nanomaterials: Synthesis, Properties, and Application (Second Edition))

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16 pages, 2893 KiB

Open AccessEditor’s ChoiceArticle

Cryo-SIMPLY: A Reliable STT-MRAM-Based Smart Material Implication Architecture for In-Memory Computing

by Tatiana Moposita, Esteban Garzón, Adam Teman and Marco Lanuzza

Nanomaterials 2025, 15(1), 9; https://doi.org/10.3390/nano15010009 - 25 Dec 2024

Viewed by 990

Abstract

This paper presents Cryo-SIMPLY, a reliable smart material implication (SIMPLY) operating at cryogenic conditions (77 K). The assessment considers SIMPLY schemes based on spin-transfer torque magnetic random access memory (STT-MRAM) technology with single-barrier magnetic tunnel junction (SMTJ) and double-barrier magnetic tunnel junction (DMTJ). [...] Read more.

This paper presents Cryo-SIMPLY, a reliable smart material implication (SIMPLY) operating at cryogenic conditions (77 K). The assessment considers SIMPLY schemes based on spin-transfer torque magnetic random access memory (STT-MRAM) technology with single-barrier magnetic tunnel junction (SMTJ) and double-barrier magnetic tunnel junction (DMTJ). Our study relies on a temperature-aware macrospin-based Verilog-A compact model for MTJ devices and a 65 nm commercial process design kit (PDK) calibrated down to 77 K under silicon measurements. The DMTJ-based SIMPLY demonstrates a significant improvement in read margin at 77 K, overcoming the conventional SIMPLY scheme at room temperature (300 K) by approximately 2.3 X. When implementing logic operations with the SIMPLY scheme operating at 77 K, the DMTJ-based scheme assures energy savings of about 69%, as compared to its SMTJ-based counterpart operating at 77 K. Overall, our results prove that the SIMPLY scheme at cryogenic conditions is a promising solution for reliable and energy-efficient logic-in-memory (LIM) architectures. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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21 pages, 3805 KiB

Open AccessEditor’s ChoiceArticle

Embedment of Biosynthesised Silver Nanoparticles in PolyNIPAAm/Chitosan Hydrogel for Development of Proactive Smart Textiles

by Dominika Glažar, Danaja Štular, Ivan Jerman, Barbara Simončič and Brigita Tomšič

Nanomaterials 2025, 15(1), 10; https://doi.org/10.3390/nano15010010 - 25 Dec 2024

Cited by 1 | Viewed by 672

Abstract

A smart viscose fabric with temperature and pH responsiveness and proactive antibacterial and UV protection was developed. PNCS (poly-(N-isopropylakrylamide)/chitosan) hydrogel was used as the carrier of silver nanoparticles (Ag NPs), synthesised in an environmentally friendly manner using AgNO₃ and a sumac leaf [...] Read more.

A smart viscose fabric with temperature and pH responsiveness and proactive antibacterial and UV protection was developed. PNCS (poly-(N-isopropylakrylamide)/chitosan) hydrogel was used as the carrier of silver nanoparticles (Ag NPs), synthesised in an environmentally friendly manner using AgNO₃ and a sumac leaf extract. PNCS hydrogel and Ag NPs were applied to the viscose fabric by either in situ synthesis of Ag NPs on the surface of viscose fibres previously modified with PNCS hydrogel, or by the direct immobilisation of Ag NPs by the dehydration/hydration of the PNCS hydrogel with the nanodispersion of Ag NPs in the sumac leaf extract and subsequent application to the viscose fibres. Compared to the pre-functionalised PNCS application method, the in situ functionalisation imparted much higher concentration of Ag NPs on the fibres, colouring the samples brown to brown-green. These samples showed more than 90% reduction in the test bacteria E. coli and S. aureus and provided excellent UV protection. In this case, the PNCS hydrogel acted as a reservoir for Ag NPs, whose release was based on a diffusion-controlled mechanism. Despite the Ag NPs decreasing the responsiveness of the PNCS hydrogel, the moisture management was still preserved in the modified samples. Accordingly, the PNCS hydrogel is a suitable carrier for biosynthesized Ag NPs to tailor the protective smart surface of viscose fibres. Full article

(This article belongs to the Special Issue Antimicrobial and Antioxidant Activity of Nanoparticles)

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22 pages, 11586 KiB

Open AccessEditor’s ChoiceReview

New Strategy for Microbial Corrosion Protection: Photocatalytic Antimicrobial Quantum Dots

by Shijia Liu, Dapeng Wu, Jie Zheng, Baochen Han, Jian Qi, Fanchun Meng, Jianhui Li and Dan Liu

Nanomaterials 2025, 15(1), 2; https://doi.org/10.3390/nano15010002 - 24 Dec 2024

Viewed by 1136

Abstract

Microbial corrosion has significant implications for the economy, environment, and human safety worldwide. Photocatalytic antibacterial technology, owing to its advantages in environmental protection, broad-spectrum, and efficient sterilization, presents a compelling alternative to traditional antibacterial strategies for microbial corrosion protection. In recent years, photocatalytic [...] Read more.

Microbial corrosion has significant implications for the economy, environment, and human safety worldwide. Photocatalytic antibacterial technology, owing to its advantages in environmental protection, broad-spectrum, and efficient sterilization, presents a compelling alternative to traditional antibacterial strategies for microbial corrosion protection. In recent years, photocatalytic quantum dot materials have garnered considerable attention in this field due to their unique quantum effects. This article provides a brief overview of the quantum effects associated with quantum dot materials, reviews the classification and preparation methods of these photocatalytic quantum dots, and elucidates their inhibitory effects and mechanisms against microbial corrosion. Finally, this article summarizes unresolved issues and prospects for the future development of quantum dots in the realm of microbial corrosion protection. Full article

(This article belongs to the Special Issue Anticorrosive Nanomaterials and Nanostructured Coatings)

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15 pages, 8375 KiB

Open AccessEditor’s ChoiceArticle

Nanodots of Transition Metal Sulfides, Carbonates, and Oxides Obtained Through Spontaneous Co-Precipitation with Silica

by Bastian Rödig, Diana Funkner, Thomas Frank, Ulrich Schürmann, Julian Rieder, Lorenz Kienle, Werner Kunz and Matthias Kellermeier

Nanomaterials 2024, 14(24), 2054; https://doi.org/10.3390/nano14242054 - 23 Dec 2024

Viewed by 930

Abstract

The controlled formation and stabilization of nanoparticles is of fundamental relevance for materials science and key to many modern technologies. Common synthetic strategies to arrest growth at small sizes and prevent undesired particle agglomeration often rely on the use of organic additives and [...] Read more.

The controlled formation and stabilization of nanoparticles is of fundamental relevance for materials science and key to many modern technologies. Common synthetic strategies to arrest growth at small sizes and prevent undesired particle agglomeration often rely on the use of organic additives and require non-aqueous media and/or high temperatures, all of which appear critical with respect to production costs, safety, and sustainability. In the present work, we demonstrate a simple one-pot process in water under ambient conditions that can produce particles of various transition metal carbonates and sulfides with sizes of only a few nanometers embedded in a silica shell, similar to particles derived from more elaborate synthesis routes, like the sol–gel process. To this end, solutions of soluble salts of metal cations (e.g., chlorides) and the respective anions (e.g., sodium carbonate or sulfide) are mixed in the presence of different amounts of sodium silicate at elevated pH levels. Upon mixing, metal carbonate/sulfide particles nucleate, and their subsequent growth causes a sensible decrease of pH in the vicinity. Dissolved silicate species respond to this local acidification by condensation reactions, which eventually lead to the formation of amorphous silica layers that encapsulate the metal carbonate/sulfide cores and, thus, effectively inhibit any further growth. The as-obtained carbonate nanodots can readily be converted into the corresponding metal oxides by secondary thermal treatment, during which their nanometric size is maintained. Although the described method clearly requires optimization towards actual applications, the results of this study highlight the potential of bottom-up self-assembly for the synthesis of functional nanoparticles at mild conditions. Full article

(This article belongs to the Section Inorganic Materials and Metal-Organic Frameworks)

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19 pages, 3781 KiB

Open AccessEditor’s ChoiceArticle

Constructing Dynamical Symmetries for Quantum Computing: Applications to Coherent Dynamics in Coupled Quantum Dots

by James R. Hamilton, Raphael D. Levine and Francoise Remacle

Nanomaterials 2024, 14(24), 2056; https://doi.org/10.3390/nano14242056 - 23 Dec 2024

Cited by 1 | Viewed by 716

Abstract

Dynamical symmetries, time-dependent operators that almost commute with the Hamiltonian, extend the role of ordinary symmetries. Motivated by progress in quantum technologies, we illustrate a practical algebraic approach to computing such time-dependent operators. Explicitly we expand them as a linear combination of time-independent [...] Read more.

Dynamical symmetries, time-dependent operators that almost commute with the Hamiltonian, extend the role of ordinary symmetries. Motivated by progress in quantum technologies, we illustrate a practical algebraic approach to computing such time-dependent operators. Explicitly we expand them as a linear combination of time-independent operators with time-dependent coefficients. There are possible applications to the dynamics of systems of coupled coherent two-state systems, such as qubits, pumped by optical excitation and other addressing inputs. Thereby, the interaction of the system with the excitation is bilinear in the coherence between the two states and in the strength of the time-dependent excitation. The total Hamiltonian is a sum of such bilinear terms and of terms linear in the populations. The terms in the Hamiltonian form a basis for Lie algebra, which can be represented as coupled individual two-state systems, each using the population and the coherence between two states. Using the factorization approach of Wei and Norman, we construct a unitary quantum mechanical evolution operator that is a factored contribution of individual two-state systems. By that one can accurately propagate both the wave function and the density matrix with special relevance to quantum computing based on qubit architecture. Explicit examples are derived for the electronic dynamics in coupled semi-conducting nanoparticles that can be used as hardware for quantum technologies. Full article

(This article belongs to the Special Issue Quantum Computing and Nanomaterial Simulations)

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13 pages, 3253 KiB

Open AccessEditor’s ChoiceArticle

Effects of Au Addition on the Performance of Thermal Electronic Noses Based on Porous Cu₂O–SnO₂ Nanospheres

by Matteo Tonezzer, Taro Ueda, Soichiro Torai, Koki Fujita, Yasuhiro Shimizu and Takeo Hyodo

Nanomaterials 2024, 14(24), 2052; https://doi.org/10.3390/nano14242052 - 22 Dec 2024

Viewed by 747

Abstract

The electronic nose is an increasingly useful tool in many fields and applications. Our thermal electronic nose approach, based on nanostructured metal oxide chemiresistors in a thermal gradient, has the advantage of being tiny and therefore integrable in portable and wearable devices. Obviously, [...] Read more.

The electronic nose is an increasingly useful tool in many fields and applications. Our thermal electronic nose approach, based on nanostructured metal oxide chemiresistors in a thermal gradient, has the advantage of being tiny and therefore integrable in portable and wearable devices. Obviously, a wise choice of the nanomaterial is crucial for the device’s performance and should therefore be carefully considered. Here we show how the addition of different amounts of Au (between 1 and 5 wt%) on Cu₂O–SnO₂ nanospheres affects the thermal electronic nose performance. Interestingly, the best performance is not achieved with the material offering the highest intrinsic selectivity. This confirms the importance of specific studies, since the performance of chemoresistive gas sensors does not linearly affect the performance of the electronic nose. By optimizing the amount of Au, the device achieved a perfect classification of the tested gases (acetone, ethanol, and toluene) and a good concentration estimation (with a mean absolute percentage error around 16%). These performances, combined with potentially smaller dimensions of less than 0.5 mm², make this thermal electronic nose an ideal candidate for numerous applications, such as in the agri-food, environmental, and biomedical sectors. Full article

(This article belongs to the Section Environmental Nanoscience and Nanotechnology)

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36 pages, 8819 KiB

Open AccessEditor’s ChoiceReview

Harnessing Radiation for Nanotechnology: A Comprehensive Review of Techniques, Innovations, and Application

by Mobinul Islam, Md. Shahriar Ahmed, Sua Yun, Hae-Yong Kim and Kyung-Wan Nam

Nanomaterials 2024, 14(24), 2051; https://doi.org/10.3390/nano14242051 - 21 Dec 2024

Viewed by 1977

Abstract

Nanomaterial properties such as size, structure, and composition can be controlled by manipulating radiation, such as gamma rays, X-rays, and electron beams. This control allows scientists to create materials with desired properties that can be used in a wide range of applications, from [...] Read more.

Nanomaterial properties such as size, structure, and composition can be controlled by manipulating radiation, such as gamma rays, X-rays, and electron beams. This control allows scientists to create materials with desired properties that can be used in a wide range of applications, from electronics to medicine. This use of radiation for nanotechnology is revolutionizing the way we design and manufacture materials. Additionally, radiation-induced nanomaterials are more cost effective and energy efficient. This technology is also having a positive impact on the environment, as materials are being produced with fewer emissions, less energy, and less waste. This cutting-edge technology is opening up new possibilities and has become an attractive option for many industries, from medical advancements to energy storage. It is also helping to make the world a better place by reducing our carbon footprint and preserving natural resources. This review aims to meticulously point out the synthesis approach and highlights significant progress in generating radiation-induced nanomaterials with tunable and complex morphologies. This comprehensive review article is essential for researchers to design innovative materials for advancements in health care, electronics, energy storage, and environmental remediation. Full article

(This article belongs to the Special Issue Radiation Technology in Nanomaterials)

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17 pages, 4113 KiB

Open AccessEditor’s ChoiceReview

Electron Holography for Advanced Characterization of Permanent Magnets: Demagnetization Field Mapping and Enhanced Precision in Phase Analysis

by Sujin Lee

Nanomaterials 2024, 14(24), 2046; https://doi.org/10.3390/nano14242046 - 20 Dec 2024

Viewed by 882

Abstract

This review explores a method of visualizing a demagnetization field (H_d) within a thin-foiled Nd₂Fe₁₄B specimen using electron holography observation. Mapping the H_d is critical in electron holography as it provides the only information on [...] Read more.

This review explores a method of visualizing a demagnetization field (H_d) within a thin-foiled Nd₂Fe₁₄B specimen using electron holography observation. Mapping the H_d is critical in electron holography as it provides the only information on magnetic flux density. The H_d map within a Nd₂Fe₁₄B thin foil, derived from this method, showed good agreement with the micromagnetic simulation result, providing valuable insights related to coercivity. Furthermore, this review examines the application of the wavelet hidden Markov model (WHMM) for noise suppression in thin-foiled Nd₂Fe₁₄B crystals. The results show significant suppression of artificial phase jumps in the reconstructed phase images due to the poor visibility of electron holograms under the narrowest fringe spacing required for spatial resolution in electron holography. These techniques substantially enhance the precision of phase analysis and are applicable to a wide range of magnetic materials, enabling more accurate magnetic characterization. Full article

(This article belongs to the Special Issue Exploring Nanomaterials through Electron Microscopy and Spectroscopy)

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14 pages, 12358 KiB

Open AccessEditor’s ChoiceArticle

Oxygenated VOC Detection Using SnO₂ Nanoparticles with Uniformly Dispersed Bi₂O₃

by Haoyue Yang, Koichi Suematsu, Felipe Hiroshi Mashiba, Ken Watanabe and Kengo Shimanoe

Nanomaterials 2024, 14(24), 2032; https://doi.org/10.3390/nano14242032 - 18 Dec 2024

Cited by 1 | Viewed by 883

Abstract

Bi₂O₃ particles are introduced as foreign additives onto SnO₂ nanoparticles (NPs) surfaces for the efficient detection of oxygenated volatile organic compounds (VOCs). Bi₂O₃-loaded SnO₂ materials are prepared via the impregnation method followed by calcination [...] Read more.

Bi₂O₃ particles are introduced as foreign additives onto SnO₂ nanoparticles (NPs) surfaces for the efficient detection of oxygenated volatile organic compounds (VOCs). Bi₂O₃-loaded SnO₂ materials are prepared via the impregnation method followed by calcination treatment. The abundant Bi₂O₃/SnO₂ interfaces are constructed by the uniform dispersion of Bi₂O₃ particles on the SnO₂ surface. The results of oxygen temperature-programmed desorption suggest that Bi₂O₃-loaded SnO₂ samples display improved surface oxygen ions than neat-SnO₂ NPs. As a result, the gas sensor based on 1 mol% Bi₂O₃-loaded SnO₂ (1Bi-L-SnO₂) composites shows significantly higher sensitivity and a faster response speed toward various oxygenated VOCs compared with SnO₂, especially at 200 °C and 250 °C. The results of catalytic combustion and temperature-programmed reaction measurements reveal the dominant role of adsorption and partial oxidation during ethanol combustion on SnO₂ and 1Bi-L-SnO₂ surfaces. In this case, the improvement in the sensing performance of the 1Bi-L-SnO₂ sensor can be associated with the increase in surface oxygen ions at Bi₂O₃/SnO₂ interfaces. The results confirm the significant role of surface functionalization for sensing materials. The obtained outstanding sensing performance provides the potential application for the simultaneous detection of total oxygenated VOCs in practice. Full article

(This article belongs to the Special Issue Nanostructured Materials in Gas Sensing Applications)

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14 pages, 2397 KiB

Open AccessEditor’s ChoiceArticle

Controllable Growth of Monolayer and Bilayer WSe₂ by Liquid-Phase Precursor via Chemical Vapor Deposition for Photodetection

by Siyuan Wang, Pinyi Wang, Hailun Tang, Shilong Yu, Huihui Ye, Xinyu Fang, Jing Ding, Yang Yang and Hai Li

Nanomaterials 2024, 14(24), 2021; https://doi.org/10.3390/nano14242021 - 16 Dec 2024

Viewed by 1139

Abstract

Two-dimensional WSe₂ nanosheets have received increasing attention due to their excellent optoelectronic properties. Solid precursors, such as WO₃ and Se powders, have been extensively employed to grow WSe₂ nanosheets by the chemical vapor deposition (CVD) method. However, the high melting [...] Read more.

Two-dimensional WSe₂ nanosheets have received increasing attention due to their excellent optoelectronic properties. Solid precursors, such as WO₃ and Se powders, have been extensively employed to grow WSe₂ nanosheets by the chemical vapor deposition (CVD) method. However, the high melting point of WO₃ results in heterogeneous nucleation sites and nonuniform growth of the WSe₂ nanosheet. By dissolving WO₃ powder in a NaOH solution, we report a facile and uniform growth of monolayer and bilayer WSe₂ nanosheets on a SiO₂/Si substrate at a large scale using liquid precursor by the CVD method. The size and thickness of the WSe₂ nanosheets were controlled by modulating the precursor concentration and growth temperature. The as-prepared monolayer and bilayer WSe₂ nanosheets were well characterized by optical microscopy, atomic force microscopy, and Raman and photoluminescence spectroscopy. With the increase in precursor concentration, the size of the monolayer WSe₂ increased up to 120 μm. Bilayer WSe₂ nanosheets were grown at higher temperatures. The photosensitivity of the bilayer WSe₂ was one order of magnitude higher than that of the monolayer WSe₂. The carrier mobility, specific detectivity, photoresponsivity, and external quantum efficiency of the bilayer WSe₂ were about two orders of magnitude higher than those of the monolayer WSe₂. Our method opens up a new avenue to grow monolayer and bilayer WSe₂ for optoelectronic applications. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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15 pages, 5399 KiB

Open AccessEditor’s ChoiceArticle

Studies on Morphological Evolution of Gravure-Printed ZnO Thin Films Induced by Low-Temperature Vapor Post-Treatment

by Giuliano Sico, Vincenzo Guarino, Carmela Borriello and Maria Montanino

Nanomaterials 2024, 14(24), 2006; https://doi.org/10.3390/nano14242006 - 13 Dec 2024

Viewed by 966

Abstract

In recent years, the morphology control of semiconductor nanomaterials has been attracting increasing attention toward maximizing their functional properties and reaching their end use in real-world devices. However, the development of easy and cost-effective methods for preparing large-scale patterned semiconductor structures on flexible [...] Read more.

In recent years, the morphology control of semiconductor nanomaterials has been attracting increasing attention toward maximizing their functional properties and reaching their end use in real-world devices. However, the development of easy and cost-effective methods for preparing large-scale patterned semiconductor structures on flexible temperature-sensitive substrates remains ever in demand. In this study, vapor post-treatment (VPT) is investigated as a potential, simple and low-cost post-preparative method to morphologically modify gravure-printed zinc oxide (ZnO) nanoparticulate thin films at low temperatures. Exposing nanoparticles (NPs) to acidic vapor solution, spontaneous restructuring pathways are observed as a consequence of NPs tending to reduce their high interfacial energy. Depending on the imposed environmental conditions during the treatment (e.g., temperature, vapor composition), various ZnO thin-film morphologies are produced, from dense to porous ones, as a result of the activation and interplay of different spontaneous interface elimination mechanisms, including dissolution–precipitation, grain boundary migration and grain rotation–coalescence. The influence of VPT on structural/optical properties has been examined via XRD, UV–visible and photoluminescence measurements. Controlling NP junctions and network nanoporosity, VPT appears as promising cost-effective, low-temperature and pressureless post-preparative platform for preparing supported ZnO NP-based films with improved connectivity and mechanical stability, favoring their practical use and integration in flexible devices. Full article

(This article belongs to the Section Physical Chemistry at Nanoscale)

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13 pages, 1050 KiB

Open AccessEditor’s ChoiceArticle

Exploring Gluconamide-Modified Silica Nanoparticles of Different Sizes as Effective Carriers for Antimicrobial Photodynamic Therapy

by Ruth Prieto-Montero, Lucia Herrera, Maite Tejón, Andrea Albaya, Jose Luis Chiara, Mónica L. Fanarraga and Virginia Martínez-Martínez

Nanomaterials 2024, 14(24), 1982; https://doi.org/10.3390/nano14241982 - 11 Dec 2024

Viewed by 1196

Abstract

Antimicrobial resistance (AMR), a consequence of the ability of microorganisms, especially bacteria, to develop resistance against conventional antibiotics, hampering the treatment of common infections, is recognized as one of the most imperative health threats of this century. Antibacterial photodynamic therapy (aPDT) has emerged [...] Read more.

Antimicrobial resistance (AMR), a consequence of the ability of microorganisms, especially bacteria, to develop resistance against conventional antibiotics, hampering the treatment of common infections, is recognized as one of the most imperative health threats of this century. Antibacterial photodynamic therapy (aPDT) has emerged as a promising alternative strategy, utilizing photosensitizers activated by light to generate reactive oxygen species (ROS) that kill pathogens without inducing resistance. In this work, we synthesized silica nanoparticles (NPs) of different sizes (20 nm, 80 nm, and 250 nm) functionalized with the photosensitizer Rose Bengal (RB) and a gluconamide ligand, which targets Gram-negative bacteria, to assess their potential in aPDT. Comprehensive characterization, including dynamic light scattering (DLS) and photophysical analysis, confirmed the stability and effective singlet oxygen production of the functionalized nanoparticles. Although the surface loading density of Rose Bengal was constant at the nanoparticle external surface, RB loading (in mg/g nanoparticle) was size-dependent, decreasing with increasing nanoparticle diameter. Further, the spherical geometry of nanoparticles favored smaller nanoparticles for antibacterial PDT, as this maximizes the surface contact area with the bacteria wall, with the smallest (20 nm) and intermediate (80 nm) particles being more promising. Bacterial assays in E. coli revealed minimal dark toxicity and significant light-activated phototoxicity for the RB-loaded nanoparticles. The addition of gluconamide notably enhanced phototoxic activity, particularly in the smallest nanoparticles (RB-G-20@SiNP), which demonstrated the highest phototoxicity-to-cytotoxicity ratio. These findings indicate that small, gluconamide-functionalized silica nanoparticles are highly effective for targeted aPDT, offering a robust strategy to combat AMR. Full article

(This article belongs to the Special Issue Nanotechnology Applied in Modern Photodynamic Therapy)

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14 pages, 3727 KiB

Open AccessEditor’s ChoiceArticle

Engineering Zn/Fe Mixed Metal Oxides with Tunable Structural and Magnetic Properties for Magnetic Particle Imaging

by Qianyi Zhang, Bing Sun, Saeed Shanehsazzadeh, Andre Bongers and Zi Gu

Nanomaterials 2024, 14(23), 1964; https://doi.org/10.3390/nano14231964 - 7 Dec 2024

Viewed by 1100

Abstract

Engineering magnetic nanoparticles with tunable structural properties and magnetism is critical to develop desirable magnetic particle imaging (MPI) tracers for biomedical applications. Here we present a new superparamagnetic metal oxide nanoparticle with a controllable chemical composition and magnetism for imaging tumor xenografts in [...] Read more.

Engineering magnetic nanoparticles with tunable structural properties and magnetism is critical to develop desirable magnetic particle imaging (MPI) tracers for biomedical applications. Here we present a new superparamagnetic metal oxide nanoparticle with a controllable chemical composition and magnetism for imaging tumor xenografts in living mice. Superparamagnetic Zn/Fe mixed metal oxide (ZnFe-MMO) nanoparticles are fabricated via a facile one-pot co-precipitation method in water followed by thermal decomposition with tunable Zn/Fe ratios and at various calcination temperatures. This work, for the first time, presented LDH-derived metal oxides for an MPI application. The metal composition is tunable to present an optimized MPI performance. The analytical results demonstrate that ZnFe-MMO nanoparticles at the designed molar ratio of Zn/Fe = 2:1 after 650 °C calcination demonstrate a higher saturation magnetization (M_S) value and optimal MPI signal than the samples presented with other conditions. The excellent biocompatibility of ZnFe-MMO is demonstrated in both breast cancer cells and fibroblast cell cultures. In vivo imaging of 4T1 tumor xenografts in mice using ZnFe-MMO as a tracer showed that the mean signal intensity is 1.27-fold higher than the commercial tracer VivoTrax at 72 h post-injection, indicating ZnFe-MMO’s promise for prolonged MPI imaging applications. Full article

(This article belongs to the Collection Magnetic Nanostructured Materials: Synthesis, Characterization and Their Cutting-Edge Applications)

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22 pages, 2685 KiB

Open AccessEditor’s ChoiceReview

Recent Advances in DNA Origami-Enabled Optical Biosensors for Multi-Scenario Application

by Ziao Hao, Lijun Kong, Longfei Ruan and Zhengtao Deng

Nanomaterials 2024, 14(23), 1968; https://doi.org/10.3390/nano14231968 - 7 Dec 2024

Viewed by 1720

Abstract

Over the past few years, significant progress has been made in DNA origami technology due to the unrivaled self-assembly properties of DNA molecules. As a highly programmable, addressable, and biocompatible nanomaterial, DNA origami has found widespread applications in biomedicine, such as cell scaffold [...] Read more.

Over the past few years, significant progress has been made in DNA origami technology due to the unrivaled self-assembly properties of DNA molecules. As a highly programmable, addressable, and biocompatible nanomaterial, DNA origami has found widespread applications in biomedicine, such as cell scaffold construction, antimicrobial drug delivery, and supramolecular enzyme assembly. To expand the scope of DNA origami application scenarios, researchers have developed DNA origami structures capable of actively identifying and quantitatively reporting targets. Optical DNA origami biosensors are promising due to their fast-to-use, sensitive, and easy implementation. However, the conversion of DNA origami to optical biosensors is still in its infancy stage, and related strategies have not been systematically summarized, increasing the difficulty of guiding subsequent researchers. Therefore, this review focuses on the universal strategies that endow DNA origami with dynamic responsiveness from both de novo design and current DNA origami modification. Various applications of DNA origami biosensors are also discussed. Additionally, we highlight the advantages of DNA origami biosensors, which offer a single-molecule resolution and high signal-to-noise ratio as an alternative to traditional analytical techniques. We believe that over the next decade, researchers will continue to transform DNA origami into optical biosensors and explore their infinite possible uses. Full article

(This article belongs to the Section Biology and Medicines)

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25 pages, 6294 KiB

Open AccessEditor’s ChoiceArticle

Transition to Metallic and Superconducting States Induced by Thermal or Electrical Deoxidation of the Dislocation Network in the Surface Region of SrTiO₃

by Krzysztof Szot, Christian Rodenbücher, Krzysztof Rogacki, Gustav Bihlmayer, Wolfgang Speier, Krystian Roleder, Franciszek Krok, Hugo Keller, Arndt Simon and Annette Bussmann-Holder

Nanomaterials 2024, 14(23), 1944; https://doi.org/10.3390/nano14231944 - 4 Dec 2024

Viewed by 1019

Abstract

The question as to why deoxidized SrTiO_3−δ becomes metallic and superconducting at extremely low levels of oxygen vacancy concentration has been a mystery for many decades. Here, we show that the real amount of effused oxygen during thermal reduction, which is needed [...] Read more.

The question as to why deoxidized SrTiO_3−δ becomes metallic and superconducting at extremely low levels of oxygen vacancy concentration has been a mystery for many decades. Here, we show that the real amount of effused oxygen during thermal reduction, which is needed to induce superconducting properties, is in the range of only 10¹⁴/cm³ and thus even lower than the critical carrier concentrations assumed previously (10¹⁷–10¹⁹/cm³). By performing detailed investigations of the optical and electrical properties down to the nanoscale, we reveal that filaments are forming during reduction along a network of dislocations in the surface layer. Hence, a reduced epi-polished SrTiO_3−δ crystal has to be regarded as a nano-composite consisting of a perfect dielectric matrix with negligible carrier density, which is short-circuited by metallic filaments with a local carrier density in the range of 10²⁰/cm³. We present that electro-degradation leads to a more pronounced evolution of filamentary bundles and thus can generate a superconducting state with higher T_C than thermal reduction. These findings indicate that traditional homogeneous models of superconductivity in self-doped SrTiO_3−δ need to be revised, and we propose an alternative explanation taking into account the coexistence of metallic dislocation cores with polar insulating regions allowing for polaronic coupling. Full article

(This article belongs to the Special Issue Recent Advances in Nanowires and Superconductors (Second Edition))

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14 pages, 2662 KiB

Open AccessEditor’s ChoiceArticle

Tribological and Heat Transfer Investigation of Graphene Oxide Coatings on Nylon Rotating Bands in an Artillery System

by Hongbin Chen, Zeyang Meng and Shuang Yi

Nanomaterials 2024, 14(23), 1943; https://doi.org/10.3390/nano14231943 - 3 Dec 2024

Cited by 1 | Viewed by 926

Abstract

Exploring ways to improve the performance of rotating bands is of great importance for enhancing the power of modern artillery. This study prepared graphene oxide-coated Nylon (GO-Nylon) and Nylon samples based on nylon rotating bands in artillery systems to investigate the feasibility of [...] Read more.

Exploring ways to improve the performance of rotating bands is of great importance for enhancing the power of modern artillery. This study prepared graphene oxide-coated Nylon (GO-Nylon) and Nylon samples based on nylon rotating bands in artillery systems to investigate the feasibility of introducing GO-coated nylon rotating band materials to enhance their tribological and thermal properties. The friction behavior and thermal effects of these two surfaces were analyzed under different external loads and surface roughness conditions. The results show that the excellent thermal conductivity of GO effectively reduced temperature accumulation during friction. Under an external load of 8 N, the surface temperature of GO-Nylon decreased by 14% compared to the Nylon surface, and the coefficient of friction (COF) decreased by 21%. At the same time, a simulation model was established, and its calculation results were consistent with the experimental trends, providing a further explanation of the experimental phenomena. This research provides a basis for the application of graphene-based coatings in the defense industry and presents new ideas for the development of high-performance rotating band materials. Full article

(This article belongs to the Special Issue Advances in Nano-Engineered Composite Materials for Thermal Management)

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17 pages, 9772 KiB

Open AccessEditor’s ChoiceReview

Advances and Challenges in Tracking Interactions Between Plants and Metal-Based Nanoparticles

by Kena Zhang, Qingmeng Liu, Yukun Wang, Xigui Liu, Xiaoxia Zhou and Bing Yan

Nanomaterials 2024, 14(23), 1939; https://doi.org/10.3390/nano14231939 - 3 Dec 2024

Viewed by 1172

Abstract

Metal-based nanoparticles (MNPs) are increasingly prevalent in the environment due to both natural processes and human activities, leading to direct interactions with plants through soil, water, and air exposure that can have beneficial and detrimental effects on plant growth and health. Understanding the [...] Read more.

Metal-based nanoparticles (MNPs) are increasingly prevalent in the environment due to both natural processes and human activities, leading to direct interactions with plants through soil, water, and air exposure that can have beneficial and detrimental effects on plant growth and health. Understanding the uptake, translocation, and transformation of MNPs in plants is crucial for assessing environmental risks and leveraging nanotechnology in agriculture. However, accurate analysis of MNPs in plant tissues poses significant challenges due to complex plant matrices and the dynamic nature of nanoparticles. This short review summarizes recent advances in analytical methods for determining MNP–plant interactions, focusing on pre-processing and quantitative nanoparticle analysis. It highlights the importance of selecting appropriate extraction and analytical techniques to preserve nanoparticle integrity and accurate quantification. Additionally, recent advances in mass spectrometry, microscopy, and other spectroscopic techniques that improve the characterization of MNPs within plant systems are discussed. Future perspectives highlight the need to develop real-time in situ monitoring techniques and sensitive tools for characterizing nanoparticle biotransformation. Full article

(This article belongs to the Section Environmental Nanoscience and Nanotechnology)

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8 pages, 1914 KiB

Open AccessEditor’s ChoiceArticle

A Reconfigurable Polarimetric Photodetector Based on the MoS₂/PdSe₂ Heterostructure with a Charge-Trap Gate Stack

by Xin Huang, Qinghu Bai, Yang Guo, Qijie Liang, Tengzhang Liu, Wugang Liao, Aizi Jin, Baogang Quan, Haifang Yang, Baoli Liu and Changzhi Gu

Nanomaterials 2024, 14(23), 1936; https://doi.org/10.3390/nano14231936 - 1 Dec 2024

Cited by 1 | Viewed by 1158

Abstract

Besides the intensity and wavelength, the ability to analyze the optical polarization of detected light can provide a new degree of freedom for numerous applications, such as object recognition, biomedical applications, environmental monitoring, and remote sensing imaging. However, conventional filter-integrated polarimetric sensing systems [...] Read more.

Besides the intensity and wavelength, the ability to analyze the optical polarization of detected light can provide a new degree of freedom for numerous applications, such as object recognition, biomedical applications, environmental monitoring, and remote sensing imaging. However, conventional filter-integrated polarimetric sensing systems require complex optical components and a complicated fabrication process, severely limiting their on-chip miniaturization and functionalities. Herein, the reconfigurable polarimetric photodetection with photovoltaic mode is developed based on a few-layer MoS₂/PdSe₂ heterostructure channel and a charge-trap structure composed of Al₂O₃/HfO₂/Al₂O₃ (AHA)-stacked dielectrics. Because of the remarkable charge-trapping ability of carriers in the AHA stack, the MoS₂/PdSe₂ channel exhibits a high program/erase current ratio of 10⁵ and a memory window exceeding 20 V. Moreover, the photovoltaic mode of the MoS₂/PdSe₂ Schottky diode can be operated and manipulable, resulting in high and distinct responsivities in the visible broadband. Interestingly, the linear polarization of the device can be modulated under program/erase states, enabling the reconfigurable capability of linearly polarized photodetection. This study demonstrates a new prototype heterostructure-based photodetector with the capability of both tunable responsivity and linear polarization, demonstrating great potential application toward reconfigurable photosensing and polarization-resolved imaging applications. Full article

(This article belongs to the Special Issue 2D Materials for Advanced Sensors: Fabrication and Applications)

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10 pages, 2457 KiB

Open AccessEditor’s ChoiceArticle

Angle-Controlled Nanospectrum Switching from Lorentzian to Fano Lineshapes

by Fu Tang, Qinyang Zhong, Xiaoqiuyan Zhang, Yuxuan Zhuang, Tianyu Zhang, Xingxing Xu and Min Hu

Nanomaterials 2024, 14(23), 1932; https://doi.org/10.3390/nano14231932 - 30 Nov 2024

Viewed by 777

Abstract

The tunability of spectral lineshapes, ranging from Lorentzian to Fano profiles, is essential for advancing nanoscale photonic technologies. Conventional far-field techniques are insufficient for studying nanoscale phenomena, particularly within the terahertz (THz) range. In this work, we use a U-shaped resonant ring on [...] Read more.

The tunability of spectral lineshapes, ranging from Lorentzian to Fano profiles, is essential for advancing nanoscale photonic technologies. Conventional far-field techniques are insufficient for studying nanoscale phenomena, particularly within the terahertz (THz) range. In this work, we use a U-shaped resonant ring on a waveguide substrate to achieve precise modulation of Lorentzian, Fano, and antiresonance profiles. THz scattering scanning near-field optical microscopy (s-SNOM) reveals the underlying physical mechanism of these transitions, driven by time-domain phase shifts between the background excitation from the waveguide and the resonance of the U-shaped ring. Our approach reveals a pronounced asymmetry in the near-field response, which remains undetectable in far-field systems. The ability to control spectral lineshapes at the nanoscale presents promising applications in characterizing composite nanoresonators and developing nanoscale phase sensors. Full article

(This article belongs to the Special Issue Light−Matter Interactions Enabled by THz Low-Dimensional Nanophotonic Structures)

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16 pages, 5468 KiB

Open AccessEditor’s ChoiceArticle

Enhancing Methylene Blue Adsorption Performance of Ti₃C₂T_x@Sodium Alginate Foam Through Pore Structure Regulation

by Yi Hu, Hongwei Wang, Xianliang Ren, Fang Wu, Gaobin Liu, Shufang Zhang, Haijun Luo and Liang Fang

Nanomaterials 2024, 14(23), 1925; https://doi.org/10.3390/nano14231925 - 29 Nov 2024

Cited by 2 | Viewed by 1036

Abstract

Pore structural regulation is expected to be a facile way to enhance the adsorption performance of MXene. In this work, spherical foam composites consisting of Ti₃C₂T_x and sodium alginate (SA) were synthesized via a vacuum freeze-drying technique. By [...] Read more.

Pore structural regulation is expected to be a facile way to enhance the adsorption performance of MXene. In this work, spherical foam composites consisting of Ti₃C₂T_x and sodium alginate (SA) were synthesized via a vacuum freeze-drying technique. By varying the solution volume of Ti₃C₂T_x, four distinct Ti₃C₂T_x@SA spherical foams with honeycomb-like and lamellar structures with a pore diameter in the range of 100–300 μm were fabricated. Their methylene blue (MB) adsorption performances were then systematically compared. The results revealed that the honeycomb-like porous-structured spherical foams have a significantly higher adsorption capacity than their lamellar counterparts. Notably, the Ti₃C₂T_x@SA honeycomb-like porous foam exhibited a remarkable maximum adsorption capacity (q_m) of 969 mg/g, positioning it at the forefront of MB adsorbent materials. Respective analysis of the adsorption kinetics, thermodynamics, and isotherm model indicated that this MB adsorption of Ti₃C₂T_x@SA honeycomb-like porous foam is characterized to be a physical, endothermic, and monolayer adsorption. The Ti₃C₂T_x@SA honeycomb-like porous foam also demonstrated excellent resistance to ion interference and good reusability, further attesting to its substantial potential for practical applications. X-ray photoelectron spectroscopy (XPS) analysis was employed to elucidate the adsorption mechanism, which was found to involve the synergistic effect of electrostatic adsorption and amidation reaction. This work not only offers new avenues for the development of high-performance adsorption materials but also provides crucial insights into the structural design and performance optimization of porous materials. Full article

(This article belongs to the Special Issue Advanced Porous Nanomaterials: Synthesis, Properties, and Application (Second Edition))

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26 pages, 11335 KiB

Open AccessEditor’s ChoiceArticle

Water–Gas Shift over Pt Nanoparticles Dispersed on CeO₂ and Gadolinium-Doped Ceria (GDC) Supports with Specific Nano-Configurations

by Athanasios Androulakis, Ersi Nikolaraki, Catherine Drosou, Kalliopi Maria Papazisi, Stella Balomenou, Dimitrios Tsiplakides, Konstantinos G. Froudas, Pantelis N. Trikalitis, Dimitrios P. Gournis, Paraskevi Panagiotopoulou and Ioannis V. Yentekakis

Nanomaterials 2024, 14(23), 1928; https://doi.org/10.3390/nano14231928 - 29 Nov 2024

Viewed by 1085

Abstract

The water–gas shift (WGS) reaction is one of the most significant reactions in hydrogen technology since it can be used directly to produce hydrogen from the reaction of CO and water; it is also a side reaction taking place in the hydrocarbon reforming [...] Read more.

The water–gas shift (WGS) reaction is one of the most significant reactions in hydrogen technology since it can be used directly to produce hydrogen from the reaction of CO and water; it is also a side reaction taking place in the hydrocarbon reforming processes, determining their selectivity towards H₂ production. The development of highly active WGS catalysts, especially at temperatures below ~450 °C, where the reaction is thermodynamically favored but kinetically limited, remains a challenge. From a fundamental point of view, the reaction mechanism is still unclear. Since specific nanoshapes of CeO₂-based supports have recently been shown to play an important role in the performance of metal nanoparticles dispersed on their surface, in this study, a comparative study of the WGS is conducted on Pt nanoparticles dispersed (with low loading, 0.5 wt.% Pt) on CeO₂ and gadolinium-doped ceria (GDC) supports of different nano-morphologies, i.e., nanorods (NRs) and irregularly faceted particle (IRFP) CeO₂ and GDC, produced by employing hydrothermal and (co-)precipitation synthesis methods, respectively. The results showed that the support’s shape strongly affected its physicochemical properties and in turn the WGS performance of the dispersed Pt nanoparticles. Nanorod-shaped CeO_2,NRs and GDC_NRs supports presented a higher specific surface area, lower primary crystallite size and enhanced reducibility at lower temperatures compared to the corresponding irregular faceted CeO_2,IRFP and GDC_IRFP supports, leading to up to 5-fold higher WGS activity of the Pt particles supported on them. The Pt/GDC_NRs catalyst outperformed all other catalysts and exhibited excellent time-on-stream (TOS) stability. A variety of techniques, namely N₂ physical adsorption–desorption (the BET method), scanning and transmission electron microscopies (SEM and TEM), powder X-ray diffraction (PXRD) and hydrogen temperature programmed reduction (H₂-TPR), were used to identify the texture, structure, morphology and other physical properties of the materials, which together with the in situ diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) and detailed kinetic studies helped to decipher their catalytic behavior. The enhanced metal–support interactions of Pt nanoparticles with the nanorod-shaped CeO_2,NRs and GDC_NRs supports due to the creation of more active sites at the metal–support interface, leading to significantly improved reducibility of these catalysts, were concluded to be the critical factor for their superior WGS activity. Both the redox and associative reaction mechanisms proposed for WGS in the literature were found to contribute to the reaction pathway. Full article

(This article belongs to the Section Environmental Nanoscience and Nanotechnology)

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8 pages, 3953 KiB

Open AccessEditor’s ChoiceArticle

Oblique Deposited Ultra-Thin Silver Films on Polymer Gratings for Sensitive SERS Performance

by Yi-Jun Jen and Meng-Jie Lin

Nanomaterials 2024, 14(23), 1871; https://doi.org/10.3390/nano14231871 - 22 Nov 2024

Viewed by 780

Abstract

A small amount of silver was obliquely deposited onto a polymer subwavelength grating to form a metasurface that comprised silver split-tubes. An ultra-thin silver film with a monitor-controlled thickness of 20 nm at the corner of each ridge of the grating provided the [...] Read more.

A small amount of silver was obliquely deposited onto a polymer subwavelength grating to form a metasurface that comprised silver split-tubes. An ultra-thin silver film with a monitor-controlled thickness of 20 nm at the corner of each ridge of the grating provided the most sensitive surface-enhanced Raman scattering (SERS) measurements. An excitation laser beam that was incident from the substrate provided similar or better SERS enhancement than did the general configuration with the laser beam incident directly on the surface of the nanostructure. Near-field simulations were conducted to model the localized electric field enhancement and to quantify the SERS performance, demonstrating the effectiveness of this novel deposition method. Full article

(This article belongs to the Special Issue Advances and Innovations in Glancing Angle Deposition and Related Nanostructures)

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13 pages, 3209 KiB

Open AccessEditor’s ChoiceArticle

Permanent Strain Engineering of Molybdenum Disulfide Using Laser-Driven Stressors for Energy-Efficient Resistive Switching Memory Devices

by Heeyoon Jang, Seok-Ki Hyeong, Byeongjin Park, Tae-Wook Kim, Sukang Bae, Sung Kyu Jang, Yonghun Kim and Seoung-Ki Lee

Nanomaterials 2024, 14(23), 1872; https://doi.org/10.3390/nano14231872 - 22 Nov 2024

Viewed by 1084

Abstract

Strain engineering provides an attractive approach to enhance device performance by modulating the intrinsic electrical properties of materials. This is especially applicable to 2D materials, which exhibit high sensitivity to mechanical stress. However, conventional methods, such as using polymer substrates, to apply strain [...] Read more.

Strain engineering provides an attractive approach to enhance device performance by modulating the intrinsic electrical properties of materials. This is especially applicable to 2D materials, which exhibit high sensitivity to mechanical stress. However, conventional methods, such as using polymer substrates, to apply strain have limitations in that the strain is temporary and global. Here, we introduce a novel approach to induce permanent localized strain by fabricating a stressor on SiO₂/Si substrates using fiber laser irradiation, thereby enabling precise control of the surface topography. MoS₂ is transferred onto this stressor, which results in the application of ~0.8% tensile strain. To assess the impact of the internal strain on the operation of ReRAM devices, the flat-MoS₂-based and the strained-MoS₂-based devices are compared. Both devices demonstrate forming-free, bipolar, and non-volatile switching characteristics. The strained devices exhibit a 30% reduction in the operating voltage, which can be attributed to bandgap narrowing and enhanced carrier mobility. Furthermore, the strained devices exhibit nearly a two-fold improvement in endurance, presumably because of the enhanced stability from lattice release effect. These results emphasize the potential of strain engineering for advancing the performance and durability of next-generation memory devices. Full article

(This article belongs to the Special Issue Nanoelectronics: Materials, Devices and Applications (Second Edition))

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16 pages, 4681 KiB

Open AccessEditor’s ChoiceArticle

M-Doped (M = Zn, Mn, Ni) Co-MOF-Derived Transition Metal Oxide Nanosheets on Carbon Fibers for Energy Storage Applications

by Andrés González-Banciella, David Martinez-Diaz, Adrián de Hita, María Sánchez and Alejandro Ureña

Nanomaterials 2024, 14(22), 1846; https://doi.org/10.3390/nano14221846 - 19 Nov 2024

Viewed by 1230

Abstract

Carbon fiber, with its strong mechanical properties and electrical conductivity, is ideal as a fiber electrode in wearable or structural energy storage devices. However, its energy storage capacity is limited, and coatings like transition metal oxides (TMOs) enhance its electrochemical performance. Metal–organic frameworks [...] Read more.

Carbon fiber, with its strong mechanical properties and electrical conductivity, is ideal as a fiber electrode in wearable or structural energy storage devices. However, its energy storage capacity is limited, and coatings like transition metal oxides (TMOs) enhance its electrochemical performance. Metal–organic frameworks (MOFs) are commonly used to grow TMOs on carbon fibers, increasing the surface area for better energy storage. Despite this, TMOs have limited electrical conductivity, so ion exchange is often used to dope them with additional cations, improving both conductivity and energy storage capacity. This study compares different ion-exchange cations in ZIF-L-derived TMO coatings on carbon fiber. Testing both supercapacitor and Li-ion battery applications, Ni-doped samples showed superior results, attributed to their higher exchange ratio with cobalt. As a supercapacitor electrode, the Ni-doped material achieved 13.3 F/g at 50 mA/g—66% higher than undoped samples. For Li-ion battery anodes, it reached a specific capacity of 410.5 mAh/g at 25 mA/g, outperforming undoped samples by 21.4%. Full article

(This article belongs to the Special Issue Metal Organic Framework (MOF)-Based Micro/Nanoscale Materials)

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21 pages, 2882 KiB

Open AccessEditor’s ChoiceReview

Gold Nanoprobes for Robust Colorimetric Detection of Nucleic Acid Sequences Related to Disease Diagnostics

by Maria Enea, Andreia Leite, Ricardo Franco and Eulália Pereira

Nanomaterials 2024, 14(22), 1833; https://doi.org/10.3390/nano14221833 - 16 Nov 2024

Cited by 2 | Viewed by 1808

Abstract

Gold nanoparticles (AuNPs) are highly attractive for applications in the field of biosensing, particularly for colorimetric nucleic acid detection. Their unique optical properties, which are highly sensitive to changes in their environment, make them ideal candidates for developing simple, rapid, and cost-effective assays. [...] Read more.

Gold nanoparticles (AuNPs) are highly attractive for applications in the field of biosensing, particularly for colorimetric nucleic acid detection. Their unique optical properties, which are highly sensitive to changes in their environment, make them ideal candidates for developing simple, rapid, and cost-effective assays. When functionalized with oligonucleotides (Au-nanoprobes), they can undergo aggregation or dispersion in the presence of complementary sequences, leading to distinct color changes that serve as a visual signal for detection. Aggregation-based assays offer significant advantages over other homogeneous assays, such as fluorescence-based methods, namely, label-free protocols, rapid interactions in homogeneous solutions, and detection by the naked eye or using low-cost instruments. Despite promising results, the application of Au-nanoprobe-based colorimetric assays in complex biological matrices faces several challenges. The most significant are related to the colloidal stability and oligonucleotide functionalization of the Au-nanoprobes but also to the mode of detection. The type of functionalization method, type of spacer, the oligo–AuNPs ratio, changes in pH, temperature, or ionic strength influence the Au-nanoprobe colloidal stability and thus the performance of the assay. This review elucidates characteristics of the Au-nanoprobes that are determined for colorimetric gold nanoparticles (AuNPs)-based nucleic acid detection, and how they influence the sensitivity and specificity of the colorimetric assay. These characteristics of the assay are fundamental to developing low-cost, robust biomedical sensors that perform effectively in biological fluids. Full article

(This article belongs to the Special Issue Noble Metal-Based Nanostructures: Optical Properties and Applications)

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15 pages, 5249 KiB

Open AccessEditor’s ChoiceArticle

A Comprehensive Microstructure-Aware Electromigration Modeling Framework; Investigation of the Impact of Trench Dimensions in Damascene Copper Interconnects

by Ahmed Sobhi Saleh, Kristof Croes, Hajdin Ceric, Ingrid De Wolf and Houman Zahedmanesh

Nanomaterials 2024, 14(22), 1834; https://doi.org/10.3390/nano14221834 - 16 Nov 2024

Cited by 2 | Viewed by 948

Abstract

As electronic devices continue to shrink in size and increase in complexity, the current densities in interconnects drastically increase, intensifying the effects of electromigration (EM). This renders the understanding of EM crucial, due to its significant implications for device reliability and longevity. This [...] Read more.

As electronic devices continue to shrink in size and increase in complexity, the current densities in interconnects drastically increase, intensifying the effects of electromigration (EM). This renders the understanding of EM crucial, due to its significant implications for device reliability and longevity. This paper presents a comprehensive simulation framework for the investigation of EM in nano-interconnects, with a primary focus on unravelling the influential role of microstructure, by considering the impact of diffusion heterogeneity through the metal texture and interfaces. As such, the resulting atomic flux and stress distribution within nano-interconnects could be investigated. To this end, a novel approach to generate microstructures of the conductor metal is presented, whereby a predefined statistical distribution of grain sizes obtained from experimental texture analyses can be incorporated into the presented model, making the model predictive under various scales and working conditions with no need for continuous calibration. Additionally, the study advances beyond the state-of-the-art by comprehensively simulating all stages of electromigration including stress evolution, void nucleation, and void dynamics. The model was employed to study the impact of trench dimensions on the dual damascene copper texture and its impact on electromigration aging, where the model findings were corroborated by comparing them to the available experimental findings. A nearly linear increase in normalized time to nucleation was detected as the interconnect became wider with a fixed height for aspect ratios beyond 1. However, a saturation was detected with a further increase in width for lines of aspect ratios below 1, with no effective enhancement in time to nucleation. An aspect ratio of 1 seems to maximize the EM lifetime for a fixed cross-sectional area by fostering a bamboo-like structure, where about a 2-fold of increase was estimated when going from aspect ratio 2 to 1. Full article

(This article belongs to the Special Issue Mechanical and Thermal Properties of Nanomaterials)

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34 pages, 4568 KiB

Open AccessEditor’s ChoiceReview

Nanothermodynamics: There’s Plenty of Room on the Inside

by Ralph V. Chamberlin and Stuart M. Lindsay

Nanomaterials 2024, 14(22), 1828; https://doi.org/10.3390/nano14221828 - 15 Nov 2024

Cited by 1 | Viewed by 1073

Abstract

Nanothermodynamics provides the theoretical foundation for understanding stable distributions of statistically independent subsystems inside larger systems. In this review, it is emphasized that extending ideas from nanothermodynamics to simplistic models improves agreement with the measured properties of many materials. Examples include non-classical critical [...] Read more.

Nanothermodynamics provides the theoretical foundation for understanding stable distributions of statistically independent subsystems inside larger systems. In this review, it is emphasized that extending ideas from nanothermodynamics to simplistic models improves agreement with the measured properties of many materials. Examples include non-classical critical scaling near ferromagnetic transitions, thermal and dynamic behavior near liquid–glass transitions, and the 1/f-like noise in metal films and qubits. A key feature in several models is to allow separate time steps for distinct conservation laws: one type of step conserves energy and the other conserves momentum (e.g., dipole alignment). This “orthogonal dynamics” explains how the relaxation of a single parameter can exhibit multiple responses such as primary, secondary, and microscopic peaks in the dielectric loss of supercooled liquids, and the crossover in thermal fluctuations from Johnson–Nyquist (white) noise at high frequencies to 1/f-like noise at low frequencies. Nanothermodynamics also provides new insight into three basic questions. First, it gives a novel solution to Gibbs’ paradox for the entropy of the semi-classical ideal gas. Second, it yields the stable equilibrium of Ising’s original model for finite-sized chains of interacting binary degrees of freedom (“spins”). Third, it confronts Loschmidt’s paradox for the arrow of time, showing that an intrinsically irreversible step is required for maximum entropy and the second law of thermodynamics, not only in the thermodynamic limit but also in systems as small as

N = 2

particles. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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21 pages, 5741 KiB

Open AccessEditor’s ChoiceArticle

Bimetallic NiCo Nanoparticles Embedded in Organic Group Functionalized Mesoporous Silica for Efficient Hydrogen Production from Ammonia Borane Hydrolysis

by Juti Rani Deka, Diganta Saikia, Ning-Fang Lu, Chieh-Yu Chen, Hsien-Ming Kao and Yung-Chin Yang

Nanomaterials 2024, 14(22), 1818; https://doi.org/10.3390/nano14221818 - 13 Nov 2024

Viewed by 942

Abstract

In this study, bimetallic NiCo nanoparticles (NPs) were encapsulated within the mesopores of carboxylic acid functionalized mesoporous silica (CMS) through the chemical reduction approach. Both NaBH₄ and NH₃BH₃ were used as reducing agents to reduce the metal ions simultaneously. [...] Read more.

In this study, bimetallic NiCo nanoparticles (NPs) were encapsulated within the mesopores of carboxylic acid functionalized mesoporous silica (CMS) through the chemical reduction approach. Both NaBH₄ and NH₃BH₃ were used as reducing agents to reduce the metal ions simultaneously. The resulting composite was used as a catalyst for hydrolysis of ammonia borane (NH₃BH₃, AB) to produce H₂. The bimetallic NiCo NPs supported on carboxylic group functionalized mesoporous silica, referred to as Ni_xCo_100−x@CMS, exhibited significantly higher catalytic activity for AB hydrolysis compared to their monometallic counterparts. The remarkable activity of Ni_xCo_100−x@CMS could be ascribed to the synergistic contributions of Ni and Co, redox reaction during the hydrolysis, and the fine-tuned electronic structure. The catalytic performance of the Ni_xCo_100−x@CMS nanocatalyst was observed to be dependent on the composition of Ni and Co. Among all the compositions investigated, Ni₄₀Co₆₀@CMS demonstrated the highest catalytic activity, with a turn over frequency (TOF) of 18.95 mol_H2min⁻¹mol_catalyst⁻¹ and H₂ production rate of 8.0 L min⁻¹g⁻¹. The activity of Ni₄₀Co₆₀@CMS was approximately three times greater than that of Ni@CMS and about two times that of Co@CMS. The superior activity of Ni₄₀Co₆₀@CMS was attributed to its finely-tuned electronic structure, resulting from the electron transfer of Ni to Co. Furthermore, the nanocatalyst exhibited excellent durability, as the carboxylate group in the support provided a strong metal–support interaction, securely anchoring the NPs within the mesopores, preventing both agglomeration and leakage. Full article

(This article belongs to the Special Issue Applications of Nanoporous Materials in Sensors and Catalysis)

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18 pages, 4647 KiB

Open AccessEditor’s ChoiceArticle

Hematological Response to Particle Debris Generated During Wear–Corrosion Processes of CoCr Surfaces Modified with Graphene Oxide and Hyaluronic Acid for Joint Prostheses

by María L. Escudero, Maria C. García-Alonso, Belén Chico, Rosa M. Lozano, Luna Sánchez-López, Manuel Flores-Sáenz, Soledad Cristóbal-Aguado, Rafael Moreno-Gómez-Toledano and Soledad Aguado-Henche

Nanomaterials 2024, 14(22), 1815; https://doi.org/10.3390/nano14221815 - 13 Nov 2024

Viewed by 1040

Abstract

Various surface modifications to increase the lifespan of cobalt–chromium (CoCr) joint prostheses are being studied to reduce the wear rate in bone joint applications. One recently proposed modification involves depositing graphene oxide functionalized with hyaluronic acid (a compound present in joints) on CoCr [...] Read more.

Various surface modifications to increase the lifespan of cobalt–chromium (CoCr) joint prostheses are being studied to reduce the wear rate in bone joint applications. One recently proposed modification involves depositing graphene oxide functionalized with hyaluronic acid (a compound present in joints) on CoCr surfaces, which can act as a solid lubricant. This paper analyzes the biological alterations caused by wear–corrosion phenomena that occur in joints, both from the perspective of the worn surface (in vitro model) and the particles generated during the wear processes (in vivo model). The analysis of the inflammatory response of macrophage was performed on CoCr surfaces modified with graphene oxide and functionalized with hyaluronic acid (CoCr-GO-HA), before and after wear–corrosion processes. The wear particles released during the wear–corrosion tests of the CoCr-GO-HA/CoCr ball pair immersed in 3 g/L hyaluronic acid were intra-articularly injected into the experimental animals. The hematological analysis in vivo was made considering a murine model of intra-articular injection into the left knee in male adult Wistar rats, at increasing concentrations of the collected wear particles dispersed in 0.9% NaCl. Non-significant differences in the inflammatory response to unworn CoCr-GO-HA surfaces and control (polystyrene) were obtained. The wear–corrosion of the CoCr-GO-HA disk increased the inflammatory response at both 72 and 96 h of material exposure compared to the unworn CoCr-GO-HA surfaces, although the differences were not statistically significant. The pro-inflammatory response of the macrophages was reduced on the worn surfaces of the CoCr modified and functionalized with graphene oxide (GO) and hyaluronic acid (HA), compared to the worn surfaces of the unmodified CoCr. The hematological analysis and tissue reactions after intra-articular injection did not reveal pathological damage, with average hematological values recorded, although slight reductions in creatinine and protein within non-pathological ranges were found. Some traces of biomaterial particles in the knee at the highest concentration of injected particles were only found but without inflammatory signs. The results show the potential benefits of using graphene in intra-articular prostheses, which could improve the quality of life for numerous patients. Full article

(This article belongs to the Special Issue Advanced Studies in Bionanomaterials)

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20 pages, 3130 KiB

Open AccessEditor’s ChoiceArticle

Skin Sensitization Potential of Sensitizers in the Presence of Metal Oxide Nanoparticles In Vitro

by Claudia Meindl, Kristin Öhlinger, Verena Zrim, Jennifer Ober, Ramona Jeitler, Eva Roblegg and Eleonore Fröhlich

Nanomaterials 2024, 14(22), 1811; https://doi.org/10.3390/nano14221811 - 12 Nov 2024

Viewed by 1144

Abstract

Silica (SiO₂), titanium dioxide (TiO₂), and zinc oxide (ZnO) nanoparticles (NPs) are widely used in dermal products. Their skin sensitization potential, especially their effects in combination with known sensitizers, is poorly studied in vitro and their sensitization inconsistently reported [...] Read more.

Silica (SiO₂), titanium dioxide (TiO₂), and zinc oxide (ZnO) nanoparticles (NPs) are widely used in dermal products. Their skin sensitization potential, especially their effects in combination with known sensitizers, is poorly studied in vitro and their sensitization inconsistently reported in animal studies. In this study, cellular assays were used to identify different steps of sensitization, the activation of keratinocytes and dendritic cells, when cells were exposed to these NPs in the absence and presence of sensitizers. Cellular systems included HaCaT keratinocytes and U937 (U-SENS™) alone, as well as different co-culture systems of THP-1 cells with HaCaT cells (COCAT) and with primary keratinocytes. The effect of NPs differed between co-cultures and U-SENS™, whereas co-cultures with either primary keratinocytes or HaCaT cells responded similarly. Pre-exposure to ZnO NPs increased the U-SENS™ assay response to 2,4-dinitrochlorobenzene six-fold. The COCAT increase was maximally four-fold for the combination of SiO₂ and trans cinnamaldehyde. When the THP-1 cells were separated from the keratinocytes by a membrane, the response of the co-culture system was more similar to U-SENS™. The direct contact with keratinocytes decreased the modulating effect of TiO₂ and ZnO NPs but suggested an increase in response to sensitizers following dermal contact with SiO₂ NPs. Full article

(This article belongs to the Special Issue Advances in Nanotoxicology: Health and Safety)

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20 pages, 5851 KiB

Open AccessEditor’s ChoiceArticle

The Effect of Solute Elements Co-Segregation on Grain Boundary Energy and the Mechanical Properties of Aluminum by First-Principles Calculation

by Xuan Zhang, Yuxuan Wan, Cuifan Chen and Liang Zhang

Nanomaterials 2024, 14(22), 1803; https://doi.org/10.3390/nano14221803 - 11 Nov 2024

Viewed by 1116

Abstract

The segregation of solute atoms at grain boundary (GB) has an important effect on the GB characteristics and the properties of materials. The study of multielement co-segregation in GBs is still in progress and deserves further research at the atomic scale. In this [...] Read more.

The segregation of solute atoms at grain boundary (GB) has an important effect on the GB characteristics and the properties of materials. The study of multielement co-segregation in GBs is still in progress and deserves further research at the atomic scale. In this work, first-principles calculations were carried out to investigate the effect of Mg and Cu co-segregation on the energetic and mechanical properties of the Al Σ5(210) GB. The segregation tendency of Mg at the GB in the presence of Cu is characterized, indicating a preference for substitutional segregation far away from Cu atoms. Cu segregation can facilitate the segregation of Mg due to their mutual attractive energy. The GB energy results show that Mg and Cu co-segregation significantly decreases GB energy and thus enhances the stability of the Al Σ5(210) GB. First-principles tensile test calculations indicate that Cu effectively counteracts the weakening effect of Mg segregation in the GB, particularly with the high concentration of Cu segregation. The phenomenon of Cu compensating the strength of the GB is attributed to an increase of charge density and the formation of newly formed Cu-Al bonds. Conversely, Mg segregation weakens the strengthening effect of Cu on the GB, but it can increase the strength of the GB when high concentrations of Cu atoms are present in the GB. The ICOHP and Bader charge analysis exhibits that the strengthening effect of Mg is attributed to charge transfer with surrounding Al and Cu, which enhances the Cu-Al and Al-Al bonds. The results provide a further understanding of the interplay between co-segregated elements and its influence on the energetic and mechanical properties of grain boundary. Full article

(This article belongs to the Section Theory and Simulation of Nanostructures)

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12 pages, 4013 KiB

Open AccessEditor’s ChoiceArticle

Characterization of HZO Films Fabricated by Co-Plasma Atomic Layer Deposition for Ferroelectric Memory Applications

by Won-Ji Park, Ha-Jung Kim, Joung-Ho Lee, Jong-Hwan Kim, Sae-Hoon Uhm, So-Won Kim and Hee-Chul Lee

Nanomaterials 2024, 14(22), 1801; https://doi.org/10.3390/nano14221801 - 10 Nov 2024

Viewed by 1488

Abstract

Plasma-enhanced atomic layer deposition (ALD) is a common method for fabricating Hf_0.5Zr_0.5O₂ (HZO) ferroelectric thin films that can be performed using direct-plasma (DP) and remote-plasma (RP) methods. This study proposed co-plasma ALD (CPALD), where DPALD and RPALD are [...] Read more.

Plasma-enhanced atomic layer deposition (ALD) is a common method for fabricating Hf_0.5Zr_0.5O₂ (HZO) ferroelectric thin films that can be performed using direct-plasma (DP) and remote-plasma (RP) methods. This study proposed co-plasma ALD (CPALD), where DPALD and RPALD are applied simultaneously. HZO films fabricated using this method showed wake-up-free polarization properties, no anti-ferroelectricity, and high fatigue endurance when DPALD and RPALD started simultaneously. To minimize defects in the film that could negatively affect the low polarization properties and fatigue endurance, the direct plasma power was reduced to 75 W. Thus, excellent fatigue endurance for at least 10⁹ cycles was obtained under a high total remanent polarization of 47.3 μC/cm² and an applied voltage of 2.5 V. X-ray photoelectron spectroscopy and transmission electron microscopy were used to investigate the mechanisms responsible for these properties. The HZO films fabricated by CPALD contained few lattice defects (such as nonstoichiometric hafnium, nonlattice oxygen, and residual carbon) and no paraelectric phase (m-phase). This was attributed to the low-carbon residuals in the film, as high-energy activated radicals were supplied by the adsorbed precursors during film formation. This facilitated a smooth transition to the o-phase during heat treatment, which possessed ferroelectric properties. Full article

(This article belongs to the Section Nanofabrication and Nanomanufacturing)

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16 pages, 3435 KiB

Open AccessEditor’s ChoiceArticle

Harnessing a Safe Novel Lipid Nanoparticle: Targeted Oral Delivery to Colonic Epithelial and Macrophage Cells in a Colitis Mouse Model

by Rabeya Jafrin Mow, Michal Pawel Kuczma, Xiaodi Shi, Sridhar Mani, Didier Merlin and Chunhua Yang

Nanomaterials 2024, 14(22), 1800; https://doi.org/10.3390/nano14221800 - 9 Nov 2024

Viewed by 1643

Abstract

A novel lipid nanoparticle (nLNP), formulated with three essential lipids to mimic ginger-derived exosomal particles, shows strong potential for delivering IL-22 mRNA specifically to the colon, presenting a unique oral drug delivery system for inflammatory bowel disease (IBD). However, its cellular targets and [...] Read more.

A novel lipid nanoparticle (nLNP), formulated with three essential lipids to mimic ginger-derived exosomal particles, shows strong potential for delivering IL-22 mRNA specifically to the colon, presenting a unique oral drug delivery system for inflammatory bowel disease (IBD). However, its cellular targets and uptake behavior in healthy versus diseased colons remain unclear. Understanding these aspects is crucial for fully elucidating its targeting effectiveness in inflamed colon tissue. This study investigates the nLNP’s cellular targets in healthy and diseased mouse colons. Flow cytometry compared nLNP uptake in healthy mice and a DSS-induced acute colitis model. The results revealed efficient internalization of nLNP by colonic epithelial cells in healthy and inflamed mice. In non-inflamed mice, the small number of colonic macrophages resulted in minimal uptake of nLNP by these cells. In inflamed mice, macrophages migrated to the damaged epithelium, where nLNP uptake was significantly increased, highlighting the nLNP’s ability to target both epithelial and macrophage cells during inflammation. Additionally, safety assessments showed that the nLNP neither altered in vitro kinase activities nor exhibited immunotoxicity or induced in vivo toxicity at the maximum tolerated oral dose. These findings underscore the nLNP’s safety and potential as a promising epithelial/macrophage-targeted drug delivery platform for oral ulcerative colitis (UC) treatment. Full article

(This article belongs to the Special Issue Nanomaterials in Analytical Methods for Biomedical, Environmental, and Energy Applications)

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18 pages, 3362 KiB

Open AccessEditor’s ChoiceArticle

Making Mobile Nanotechnology Accessible: Is the Explicit Preparation of Janus Nanoparticle Necessary to Achieve Mobility?

by Vagisha Nidhi, Arthur Allaire, Zakariya Ait Athmane, Patrick Guenoun, Fabienne Testard, Jean-Philippe Renault and Florent Malloggi

Nanomaterials 2024, 14(22), 1796; https://doi.org/10.3390/nano14221796 - 8 Nov 2024

Viewed by 1200

Abstract

This study compares the mobility behaviour, in a H₂O₂ environment, of three different geometries of hybrid particle made of silica core functionalized by gold (nanoparticles or layer). It is known that the decomposition of H₂O₂ on gold [...] Read more.

This study compares the mobility behaviour, in a H₂O₂ environment, of three different geometries of hybrid particle made of silica core functionalized by gold (nanoparticles or layer). It is known that the decomposition of H₂O₂ on gold surfaces drives mobility; however, the link between mobility orientation and the organization of gold on silica surfaces is still questionable. While conventional wisdom posits that asymmetric designs are crucial for generating phoretic forces or localized bubble propulsion, recent research suggests that symmetrical particles may also exhibit motility. To address this debate, we developed a robust workflow for synthesizing gold grafted silica nanoparticles with precise control over size and shape, enabling the direct comparison of their motile behaviour by dynamic light scattering and particle tracking velocimetry. Our results indicate, first, that a combination of techniques is necessary to overcome their intrinsic limitation and, second, that the inherent asymmetry generated by isotropic gold nanoparticle deposition onto silica surfaces may enable particle motility. Full article

(This article belongs to the Special Issue Morphological Design and Synthesis of Nanoparticles (Second Edition))

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14 pages, 6874 KiB

Open AccessEditor’s ChoiceArticle

Fabrication of Large-Area High-Resolution Templates by Focused Ion Beam Combined with Colloidal Nanoparticle Dimer Deposition for SERS Substrates

by Liga Ignatane, Reinis Ignatans, Juris Prikulis, Annamarija Trausa, Ciro Federico Tipaldi, Edgars Vanags, Martins Zubkins, Krisjanis Smits and Anatolijs Sarakovskis

Nanomaterials 2024, 14(22), 1784; https://doi.org/10.3390/nano14221784 - 6 Nov 2024

Cited by 1 | Viewed by 1094

Abstract

This article presents an examination of well-controlled patterns created using a Ga⁺-based focused ion beam (FIB) on glass, while silicon substrates were used to evaluate the FIB performance by its achievable feature size versus time constraints. The pattern creation on glass [...] Read more.

This article presents an examination of well-controlled patterns created using a Ga⁺-based focused ion beam (FIB) on glass, while silicon substrates were used to evaluate the FIB performance by its achievable feature size versus time constraints. The pattern creation on glass was developed with the aim of studying potential surface-enhanced Raman spectroscopy (SERS) applications. Furthermore, the FIB was used to create dimer systems of periodically and randomly positioned dumbbell-shaped pits on the glass (each dimer occupies an area of 203 × 87 nm²). By following the bitmap pattern files, the FIB ensured there was 3000 dimer fabrication over a 20 × 20 μm² large area, with a pit size and position variation below 10 nm. The article highlights that FIB can be used for precise large-area nano-fabrication. The gold nanoparticle dimers were formed on the prepatterned surface via capillary force-assisted deposition. The fabricated nanostructures were tested in SERS measurements. The enhancement factor for Rhodamine B molecule reached ~10⁵, demonstrating the potential application of the method to create nanostructures in the sensor domain. Full article

(This article belongs to the Collection Editorial Board Members’ Collection Series in “Synthesis, Structure and Application of Functional Nanocomposites”)

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18 pages, 5723 KiB

Open AccessEditor’s ChoiceArticle

Development and Biological Characterization of Cancer Biomimetic Membrane Nanovesicles for Enhancing Therapy Efficacy in Human Glioblastoma Cells

by Martina Massarotti, Paola Corna, Aromita Mallik, Gloria Milanesi, Claudio Casali, Lorenzo Magrassi and Sergio Comincini

Nanomaterials 2024, 14(22), 1779; https://doi.org/10.3390/nano14221779 - 5 Nov 2024

Viewed by 1170

Abstract

As nanocarriers of a new generation, biomimetic nanovesicles are an emerging class of therapeutic tools whose surface is integrated or fabricated with biomaterials capable of mimicking the biological features and functions of native cells. Thanks to this, biomimetic nanovesicles, in particular, those made [...] Read more.

As nanocarriers of a new generation, biomimetic nanovesicles are an emerging class of therapeutic tools whose surface is integrated or fabricated with biomaterials capable of mimicking the biological features and functions of native cells. Thanks to this, biomimetic nanovesicles, in particular, those made by plasma membrane moieties, possess greatly improved biocompatibility, high target specificity, a long retention time, and minimal undesired immune responses. For these reasons, a multitude of progenitor cells including cancer ones were employed as templates to generate biomimetic or membrane-camouflaged nanovesicles hosting different therapeutic compounds. In this contribution, different membrane-derived biomimetic vesicles (M-NVs) were generated by osmotic lysis or plasma membrane isolation approaches from normal and cancer cell lines and assayed against in vitro models of human glioblastoma. M-NVs were compared in their cellular internalization degrees of DNA and proteins, morphologically and molecularly characterized, expressing an extracellular membrane-associated marker. Then, Rose Bengal (RB), a photoactivable drug characterized by a relatively low cellular uptake, was incorporated into nascent glioblastoma-derived M-NVs and finally administered to homotypic receiving cells, showing an increased degree of internalization as well as induced cytotoxic effects, even in the absence of photodynamic direct stimulation. Similar results were also obtained assaying lyophilized M-NVs loaded with RB. In conclusion, M-NVs generated by cell membranes effectively deliver several cargoes, including therapeutic molecules, maintain functionality after lyophilization, and show significant internalization effects, making them a promising strategy for therapeutic applications against human glioblastoma cells. Full article

(This article belongs to the Special Issue The Study of the Effects of Nanoparticles on Human Cells)

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17 pages, 4451 KiB

Open AccessEditor’s ChoiceArticle

Design of Nanocrystalline Suspension of Dutasteride for Intramuscular Prolonged Delivery

by Min Young Jeong, Doe Myung Shin, Min Kyeong Kwon, Ye Bin Shin, Jun Soo Park, In Gyu Yang, Jin Hyuk Myung, Dong Geon Lee, Gi Yeong Lee, Chae Won Park, Ji Won Yeo, Myoung Jin Ho, Yong Seok Choi and Myung Joo Kang

Nanomaterials 2024, 14(22), 1781; https://doi.org/10.3390/nano14221781 - 5 Nov 2024

Viewed by 1500

Abstract

The aim of the study is to formulate an injectable nanocrystalline suspension (NS) of dutasteride (DTS), a hydrophobic 5α-reductase inhibitor used to treat benign prostatic hyperplasia and scalp hair loss, for parenteral long-acting delivery. A DTS-loaded NS (DTS-NS, 40 mg/mL DTS) was prepared [...] Read more.

The aim of the study is to formulate an injectable nanocrystalline suspension (NS) of dutasteride (DTS), a hydrophobic 5α-reductase inhibitor used to treat benign prostatic hyperplasia and scalp hair loss, for parenteral long-acting delivery. A DTS-loaded NS (DTS-NS, 40 mg/mL DTS) was prepared using a lab-scale bead-milling technique. The optimized DTS-NS prepared using Tween 80 (0.5% w/v) as a nano-suspending agent, was characterized as follows: rod/rectangular shape; particle size of 324 nm; zeta potential of −11 mV; and decreased drug crystallinity compared with intact drug powder. The DTS-NS exhibited a markedly protracted drug concentration-time profile following intramuscular injection, reaching a maximum concentration after 8.40 days, with an elimination half-life of 9.94 days in rats. Histopathological observations revealed a granulomatous inflammatory response at the injection site 7 days after intramuscular administration, which significantly subsided by day 14 and showed minimal inflammation by day 28. These findings suggest that the nanosuspension system is a promising approach for the sustained release parenteral DTS delivery, with a protracted pharmacokinetic profile and tolerable local inflammation. Full article

(This article belongs to the Special Issue Advanced Nanotechnology for Biomedical Research: Diagnosis, Drug Delivery and Targeted Therapy)

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10 pages, 2306 KiB

Open AccessEditor’s ChoiceArticle

Optimization of Thermoelectric Performance of Ag₂Te Films via a Co-Sputtering Method

by Hanwen Xu, Zhongzhao Zha, Fu Li, Guangxing Liang, Jingting Luo, Zhuanghao Zheng and Yue-Xing Chen

Nanomaterials 2024, 14(21), 1762; https://doi.org/10.3390/nano14211762 - 3 Nov 2024

Viewed by 1380

Abstract

Providing self-powered energy for wearable electronic devices is currently an important research direction in the field of thermoelectric (TE) thin films. In this study, a simple dual-source magnetron sputtering method was used to prepare Ag₂Te thin films, which exhibit good TE [...] Read more.

Providing self-powered energy for wearable electronic devices is currently an important research direction in the field of thermoelectric (TE) thin films. In this study, a simple dual-source magnetron sputtering method was used to prepare Ag₂Te thin films, which exhibit good TE properties at room temperature, and the growth temperature and subsequent annealing process were optimized to obtain high-quality films. The experimental results show that films grown at a substrate temperature of 280 °C exhibit a high power factor (PF) of ~3.95 μW/cm·K² at room temperature, which is further improved to 4.79 μW/cm·K² after optimal annealing treatment, and a highest PF of ~7.85 μW/cm·K² was observed at 200 °C. Appropriate annealing temperature effectively increases the carrier mobility of the Ag₂Te films and adjusts the Ag/Te ratio to make the composition closer to the stoichiometric ratio, thus promoting the enhancement of electrical transport properties. A TE device with five legs was assembled using as-fabricated Ag₂Te thin films. With a temperature difference of 40 K, the device was able to generate an output voltage of approximately 14.43 mV and a corresponding power of about 50.52 nW. This work not only prepared a high-performance Ag₂Te film but also demonstrated its application prospects in the field of self-powered electronic devices. Full article

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21 pages, 19527 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Three-Dimensional Printed Nanocomposites with Tunable Piezoresistive Response

by Francesca Aliberti, Liberata Guadagno, Raffaele Longo, Marialuigia Raimondo, Roberto Pantani, Andrea Sorrentino, Michelina Catauro and Luigi Vertuccio

Nanomaterials 2024, 14(21), 1761; https://doi.org/10.3390/nano14211761 - 2 Nov 2024

Cited by 3 | Viewed by 1640

Abstract

This study explores a novel approach to obtaining 3D printed strain sensors, focusing on how changing the printing conditions can produce a different piezoresistive response. Acrylonitrile butadiene styrene (ABS) filled with different weight concentrations of carbon nanotubes (CNTs) was printed in the form [...] Read more.

This study explores a novel approach to obtaining 3D printed strain sensors, focusing on how changing the printing conditions can produce a different piezoresistive response. Acrylonitrile butadiene styrene (ABS) filled with different weight concentrations of carbon nanotubes (CNTs) was printed in the form of dog bones via fused filament fabrication (FFF) using two different raster angles (0–90°). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) in TUNA mode (TUNA-AFM) were used to study the morphological features and the electrical properties of the 3D printed samples. Tensile tests revealed that sensitivity, measured by the gauge factor (G.F.), decreased with increasing filler content for both raster angles. Notably, the 90° orientation consistently showed higher sensitivity than the 0° orientation for the same filler concentration. Creep and fatigue tests identified permanent damage through residual electrical resistance values. Additionally, a cross-shaped sensor was designed to measure two-dimensional deformations simultaneously, which is applicable in the robotic field. This sensor can monitor small and large deformations in perpendicular directions by tracking electrical resistance variations in its arms, significantly expanding its measuring range. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

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29 pages, 7028 KiB

Open AccessEditor’s ChoiceReview

Recent Progress in Two-Dimensional Magnetic Materials

by Guangchao Shi, Nan Huang, Jingyuan Qiao, Xuewen Zhang, Fulong Hu, Hanwei Hu, Xinyu Zhang and Jingzhi Shang

Nanomaterials 2024, 14(21), 1759; https://doi.org/10.3390/nano14211759 - 1 Nov 2024

Cited by 2 | Viewed by 4238

Abstract

The giant magnetoresistance effect in two-dimensional (2D) magnetic materials has sparked substantial interest in various fields; including sensing; data storage; electronics; and spintronics. Their unique 2D layered structures allow for the manifestation of distinctive physical properties and precise performance regulation under different conditions. [...] Read more.

The giant magnetoresistance effect in two-dimensional (2D) magnetic materials has sparked substantial interest in various fields; including sensing; data storage; electronics; and spintronics. Their unique 2D layered structures allow for the manifestation of distinctive physical properties and precise performance regulation under different conditions. In this review, we present an overview of this rapidly developing research area. Firstly, these 2D magnetic materials are catalogued according to magnetic coupling types. Then, several vital effects in 2D magnets are highlighted together with theoretical investigation, such as magnetic circular dichroism, magneto-optical Kerr effect, and anomalous Hall effect. After that, we forecast the potential applications of 2D magnetic materials for spintronic devices. Lastly, research advances in the attracting magnons, skyrmions and other spin textures in 2D magnets are discussed. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

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21 pages, 5739 KiB

Open AccessEditor’s ChoiceArticle

Safety Evaluations of Rapamycin Perfluorocarbon Nanoparticles in Ovarian Tumor-Bearing Mice

by Qingyu Zhou, John C. Harding, Ping Fan, Ivan Spasojevic, Attila Kovacs, Antonina Akk, Adam Mitchell, Luke E. Springer, Joseph P. Gaut, Daniel A. Rauch, Samuel A. Wickline, Christine T. N. Pham, Katherine Fuh and Hua Pan

Nanomaterials 2024, 14(21), 1752; https://doi.org/10.3390/nano14211752 - 31 Oct 2024

Viewed by 1288

Abstract

Nanomedicine holds great potential for revolutionizing medical treatment. Ongoing research and advancements in nanotechnology are continuously expanding the possibilities, promising significant advancements in healthcare. To fully harness the potential of nanotechnology in medical applications, it is crucial to conduct safety evaluations for the [...] Read more.

Nanomedicine holds great potential for revolutionizing medical treatment. Ongoing research and advancements in nanotechnology are continuously expanding the possibilities, promising significant advancements in healthcare. To fully harness the potential of nanotechnology in medical applications, it is crucial to conduct safety evaluations for the nanomedicines that offer effective benefits in the preclinical stage. Our recent efficacy studies indicated that rapamycin perfluorocarbon (PFC) nanoparticles showed promise in mitigating cisplatin-induced acute kidney injury (AKI). As cisplatin is routinely administered to ovarian cancer patients as their first-line chemotherapy, in this study, we focused on evaluating the safety of rapamycin PFC nanoparticles in mice bearing ovarian tumor xenografts. Specifically, this study evaluated the effects of repeat-dose rapamycin PFC nanoparticle treatment on vital organs, the immune system, and tumor growth and assessed pharmacokinetics and biodistribution. Our results indicated that rapamycin PFC nanoparticle treatment did not cause any detectable adverse effects on cardiac, renal, or hepatic functions or on splenocyte populations, but it reduced the splenocyte secretion of IL-10, TNFα, and IL12p70 upon IgM stimulation. The pharmacokinetics and biodistribution results revealed a significant enhancement in the delivery of rapamycin to tumors by rapamycin PFC nanoparticles, which, in turn, led to a significant reduction in ovarian tumor growth. Therefore, rapamycin PFC nanoparticles have the potential to be clinically beneficial in cisplatin-treated ovarian cancer patients. Full article

(This article belongs to the Special Issue Safety and Toxicity of Carbon Nanotubes, Nanoparticles and Other Nanomaterials)

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15 pages, 4226 KiB

Open AccessEditor’s ChoiceArticle

Single Vesicle Surface Protein Profiling and Machine Learning-Based Dual Image Analysis for Breast Cancer Detection

by Mitchell Lee Taylor, Madhusudhan Alle, Raymond Wilson, Jr., Alberto Rodriguez-Nieves, Mitchell A. Lutey, William F. Slavney, Jacob Stewart, Hiyab Williams, Kristopher Amrhein, Hongmei Zhang, Yongmei Wang, Thang Ba Hoang and Xiaohua Huang

Nanomaterials 2024, 14(21), 1739; https://doi.org/10.3390/nano14211739 - 30 Oct 2024

Viewed by 1472

Abstract

Single-vesicle molecular profiling of cancer-associated extracellular vesicles (EVs) is increasingly being recognized as a powerful tool for cancer detection and monitoring. Mask and target dual imaging is a facile method to quantify the fraction of the molecularly targeted population of EVs in biofluids [...] Read more.

Single-vesicle molecular profiling of cancer-associated extracellular vesicles (EVs) is increasingly being recognized as a powerful tool for cancer detection and monitoring. Mask and target dual imaging is a facile method to quantify the fraction of the molecularly targeted population of EVs in biofluids at the single-vesicle level. However, accurate and efficient dual imaging vesicle analysis has been challenging due to the interference of false signals on the mask images and the need to analyze a large number of images in clinical samples. In this work, we report a fully automatic dual imaging analysis method based on machine learning and use it with dual imaging single-vesicle technology (DISVT) to detect breast cancer at different stages. The convolutional neural network Resnet34 was used along with transfer learning to produce a suitable machine learning model that could accurately identify areas of interest in experimental data. A combination of experimental and synthetic data were used to train the model. Using DISVT and our machine learning-assisted image analysis platform, we determined the fractions of EpCAM-positive EVs and CD24-positive EVs over captured plasma EVs with CD81 marker in the blood plasma of pilot HER2-positive breast cancer patients and compared to those from healthy donors. The amount of both EpCAM-positive and CD24-positive EVs was found negligible for both healthy donors and Stage I patients. The amount of EpCAM-positive EVs (also CD81-positive) increased from 18% to 29% as the cancer progressed from Stage II to III. No significant increase was found with further progression to Stage IV. A similar trend was found for the CD24-positive EVs. Statistical analysis showed that both EpCAM and CD24 markers can detect HER2-positive breast cancer at Stages II, III, or IV. They can also differentiate individual cancer stages except those between Stage III and Stage IV. Due to the simplicity, high sensitivity, and high efficiency, the DISVT with the AI-assisted dual imaging analysis can be widely used for both basic research and clinical applications to quantitatively characterize molecularly targeted EV subtypes in biofluids. Full article

(This article belongs to the Special Issue Extracellular Vesicles: Nanotechnology-Based Isolations, Characterizations, and Applications for Cancer Diagnostics and Monitoring)

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