Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (1,682)

Search Parameters:
Keywords = coupled nanoparticles

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
20 pages, 4676 KiB  
Article
Multifunctional, Biocompatible Hybrid Surface Coatings Combining Antibacterial, Hydrophobic and Fluorescent Applications
by Gökçe Asan and Osman Arslan
Polymers 2025, 17(15), 2139; https://doi.org/10.3390/polym17152139 - 5 Aug 2025
Abstract
The hybrid inorganic–organic material concept plays a bold role in multifunctional materials, combining different features on one platform. Once varying properties coexist without cancelling each other on one matrix, a new type of supermaterial can be formed. This concept showed that silver nanoparticles [...] Read more.
The hybrid inorganic–organic material concept plays a bold role in multifunctional materials, combining different features on one platform. Once varying properties coexist without cancelling each other on one matrix, a new type of supermaterial can be formed. This concept showed that silver nanoparticles can be embedded together with inorganic and organic surface coatings and silicon quantum dots for symbiotic antibacterial character and UV-excited visible light fluorescent features. Additionally, fluorosilane material can be coupled with this prepolymeric structure to add the hydrophobic feature, showing water contact angles around 120°, providing self-cleaning features. Optical properties of the components and the final material were investigated by UV-Vis spectroscopy and PL analysis. Atomic investigations and structural variations were detected by XPS, SEM, and EDX atomic mapping methods, correcting the atomic entities inside the coating. FT-IR tracked surface features, and statistical analysis of the quantum dots and nanoparticles was conducted. Multifunctional final materials showed antibacterial properties against E. coli and S. aureus, exhibiting self-cleaning features with high surface contact angles and visible light fluorescence due to the silicon quantum dot incorporation into the sol-gel-produced nanocomposite hybrid structure. Full article
(This article belongs to the Special Issue Polymer Coatings for High-Performance Applications)
Show Figures

Figure 1

16 pages, 4017 KiB  
Article
Recyclable Platinum Nanocatalyst for Nitroarene Hydrogenation: Gum Acacia Polymer-Stabilized Pt Nanoparticles with TiO2 Support
by Supriya Prakash, Selvakumar Ponnusamy, Jagadeeswari Rangaraman, Kundana Nakkala and Putrakumar Balla
ChemEngineering 2025, 9(4), 81; https://doi.org/10.3390/chemengineering9040081 - 30 Jul 2025
Viewed by 134
Abstract
Platinum has emerged as an optimal catalyst for the selective hydrogenation of nitroarenes owing to its high hydrogenation activity, selectivity, and stability. In this study, we report the fabrication of platinum nanoparticles stabilized on a composite support consisting of gum acacia polymer (GAP) [...] Read more.
Platinum has emerged as an optimal catalyst for the selective hydrogenation of nitroarenes owing to its high hydrogenation activity, selectivity, and stability. In this study, we report the fabrication of platinum nanoparticles stabilized on a composite support consisting of gum acacia polymer (GAP) and TiO2. It was engineered for the targeted reduction of nitroarenes to arylamines via selective hydrogenation in methanol at ambient temperature. The non-toxic and biocompatible properties of GAP enable it to act as a reducing and stabilizing agent during synthesis. The synthesized nanocatalyst was characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Morphological and structural analyses revealed that the fabricated catalyst consisted of minuscule Pt nanoparticles integrated within the GAP framework, accompanied by the corresponding TiO2 nanoparticles. Inductively coupled plasma optical emission spectrometry (ICP-OES) was employed to ascertain the Pt content. The mild reaction conditions, decent yields, trouble-free workup, and facile separation of the catalyst make this method a clean and practical alternative to nitroreduction. Selective hydrogenation yielded an average arylamine production of 97.6% over five consecutive cycles, demonstrating the stability of the nanocatalyst without detectable leaching. Full article
Show Figures

Figure 1

15 pages, 7415 KiB  
Article
Development and Protective Efficacy of a Novel Nanoparticle Vaccine for Gammacoronavirus Avain Infectious Bronchitis Virus
by Ting Xiong, Yanfen Lyu, Hongmei Li, Ting Xu, Shuting Wu, Zekun Yang, Mengyao Jing, Fei Xu, Dingxiang Liu and Ruiai Chen
Vaccines 2025, 13(8), 802; https://doi.org/10.3390/vaccines13080802 - 28 Jul 2025
Viewed by 298
Abstract
Background: Infectious bronchitis virus (IBV) is a gammacoronavirus that causes a highly contagious disease in chickens and seriously endangers the poultry industry. The GI-19 is a predominant lineage. However, no effective commercially available vaccines against this virus are available. Methods: In [...] Read more.
Background: Infectious bronchitis virus (IBV) is a gammacoronavirus that causes a highly contagious disease in chickens and seriously endangers the poultry industry. The GI-19 is a predominant lineage. However, no effective commercially available vaccines against this virus are available. Methods: In this present study, the CHO eukaryotic and the E.coli prokaryotic expression system were used to express S1-SpyTag and AP205-SpyCatcher, respectively. Subsequently, the purified S1-SpyTag and AP205-SpyCatcher were coupled to form the nanoparticles AP205-S1 (nAP205-S1) in PBS buffer at 4 °C for 48 h. S1-SpyTag and nAP205-S1 were formulated into vaccines with white oil adjuvant and employed to immunize 1-day-old SPF chickens for the comparative evaluation of their immune efficacy. Results: The nAP205-S1 vaccine in chickens induced robust IBV-specific humoral and cellular immune responses in vivo. Importantly, the humoral and cellular immune responses elicited by the nAP205-S1 vaccine were more robust than those induced by the IBV S1-SpyTag vaccine at both the same dose and double the dose, with a notably significant difference observed in the cellular immune response. Furthermore, experimental data revealed that chicken flocks vaccinated with nAP205-S1 achieved 100% group protection following a challenge, exhibiting a potent protective immune response and effectively inhibiting viral shedding. Conclusions: These results reveal the potential of developing a novel nanoparticle vaccine with broadly protective immunity against GI-19 IBV. Full article
(This article belongs to the Special Issue Vaccines for Poultry Viruses)
Show Figures

Figure 1

18 pages, 2518 KiB  
Article
NiO/TiO2 p-n Heterojunction Induced by Radiolysis for Photocatalytic Hydrogen Evolution
by Ana Andrea Méndez-Medrano, Xiaojiao Yuan, Diana Dragoe, Christophe Colbeau-Justin, José Luis Rodríguez López and Hynd Remita
Materials 2025, 18(15), 3513; https://doi.org/10.3390/ma18153513 - 26 Jul 2025
Viewed by 399
Abstract
Titanium dioxide (TiO2), a widely used semiconductor in photocatalysis owing to its adequate potential for water hydrolysis, chemical stability, low toxicity, and low cost. However, its efficiency is limited by fast charge-carrier recombination and poor visible light absorption. Coupling TiO2 [...] Read more.
Titanium dioxide (TiO2), a widely used semiconductor in photocatalysis owing to its adequate potential for water hydrolysis, chemical stability, low toxicity, and low cost. However, its efficiency is limited by fast charge-carrier recombination and poor visible light absorption. Coupling TiO2 with a p-type semiconductor, such as nickel oxide (NiO), forming a p-n heterojunction, decreases the recombination of charge carriers and increases photocatalytic activity. In this work, the surface of TiO2 modified with NiO nanoparticles (NPs) induced by radiolysis for photocatalytic hydrogen production was studied. The photocatalytic activity of NiO/TiO2 was evaluated using methanol as a hole scavenger under UV–visible light. All modified samples presented superior photocatalytic activity compared to bare TiO2. The dynamics of the charge carriers, a key electronic phenomenon in photocatalysis, was investigated by time-resolved microwave conductivity (TRMC). The results highlight the crucial role of Ni-based NPs modification in enhancing the separation of the charge carrier and activity under UV–visible irradiation. Furthermore, the results revealed that under visible irradiation, NiO-NPs inject electrons into the conduction band of titanium dioxide. Full article
(This article belongs to the Section Advanced Nanomaterials and Nanotechnology)
Show Figures

Figure 1

20 pages, 2822 KiB  
Article
Nanoparticle Formulation Generated from DDGS and Its Anthraquinone Synthesis Elicitation in Rubia tinctorum Hairy Roots
by Gonzalo Galaburri, Yazmín R. Kalapuj, María Perassolo, Julián Rodríguez Talou, Patricio G. Márquez, Romina J. Glisoni, Antonia Infantes-Molina, Enrique Rodríguez-Castellón and Juan M. Lázaro-Martínez
Polymers 2025, 17(15), 2021; https://doi.org/10.3390/polym17152021 - 24 Jul 2025
Viewed by 290
Abstract
A nanoparticle formulation was generated from distiller dried grains with solubles (DDGS), and its effect on the production of anthraquinones (AQs) was evaluated on Rubia tinctorum hairy roots. The DDGS material was washed with water and ethyl acetate to remove mainly the soluble [...] Read more.
A nanoparticle formulation was generated from distiller dried grains with solubles (DDGS), and its effect on the production of anthraquinones (AQs) was evaluated on Rubia tinctorum hairy roots. The DDGS material was washed with water and ethyl acetate to remove mainly the soluble organic/inorganic molecules and reduce the fat content, respectively, followed by an alkaline treatment to remove the polysaccharides. The resulting alkaline solutions were then lyophilized and redispersed in deionized water to generate a monodispersed nanoparticulate formulation (DDGS-NP) with a hydrodynamic diameter and zeta potential of 227 ± 42 nm and −53 ± 7 mV, respectively. The formulation demonstrated good colloidal stability over time, and sterilized DDGS-NPs maintained comparable physicochemical properties. The nanoparticles were enriched in protein fractions, unsaturated fatty acids, and orthophosphate anion components from DDGS, as determined by solid-state Nuclear Magnetic Resonance (NMR), X-ray photoelectron spectroscopy (XPS), organic elemental analysis (OEA), and inductively coupled plasma optical emission spectrometry (ICP-OES) techniques. The DDGS-NPs were tested at different concentrations on Rubia tinctorum hairy roots, in comparison to or in combination with methyl jasmonate (MeJ), for their capacity to induce the production of AQs. All DDGS-NP concentrations increased the production of specific AQs to 7.7 (100 mg L−1), 7.8 (200 mg L−1), and 9.3 µmol/gFW (500 mg L−1), with an extracellular AQ accumulation of 18 µM for the highest DDGS-NP concentration, in comparison with the control hairy roots (~2 µM AQ). The plant growth was not affected at any of the tested nanoparticle concentrations. Interestingly, the combination of DDGS-NPs and MeJ resulted in the highest extracellular AQ accumulation in R. tinctorum root cultures. Full article
(This article belongs to the Section Polymer Composites and Nanocomposites)
Show Figures

Graphical abstract

18 pages, 4044 KiB  
Article
Preparation and Immunogenicity Evaluation of a Ferritin-Based GnRH Nanoparticle Vaccine
by Ying Xu, Weihao Zhao, Yuhan Zhu, Bo Sun, Congmei Wu and Yuhe Yin
Vaccines 2025, 13(8), 781; https://doi.org/10.3390/vaccines13080781 - 23 Jul 2025
Viewed by 336
Abstract
Objectives: Research on the immunocastration vaccine is of great significance for animal management. In this study, the gonadotropin-releasing hormone (GnRH) ferritin nanoparticle vaccine was constructed using Spy Catcher-Spy Tag (SC-ST) as a delivery system; Methods: The Spy Catcher was constructed to [...] Read more.
Objectives: Research on the immunocastration vaccine is of great significance for animal management. In this study, the gonadotropin-releasing hormone (GnRH) ferritin nanoparticle vaccine was constructed using Spy Catcher-Spy Tag (SC-ST) as a delivery system; Methods: The Spy Catcher was constructed to fuse with the expression vector pET-30a-SF of ferritin nanoparticles. Two polypeptides, STG1: Spy Tag-GnRH I-PADRE and STG2: Spy Tag-GnRH I-GnRH II, coupled to SF in vitro to form two nanoparticles, were designed and synthesized to detect castration effects in mice. We mixed them with the adjuvant MONTANIDE ISA 206 VG to explore the adjuvant’s effect on immunogenicity; Results: All immunized groups produced anti-GnRH specific antibodies after the second immunization, which was significantly higher in the immunized group and the combined adjuvant group than in the control group, and the immune response could still be detected at the 12th week. The concentrations of testosterone, follicle-stimulating hormone, and luteinizing hormone in serum were significantly decreased. The number of sperm in the epididymis of mice in each immune group was significantly reduced, and the rate of sperm deformity was high; Conclusions: The two ferritin-based GnRH nanoparticles developed in this study can significantly cause testicular atrophy, decreased gonadal hormone concentration, decreased sperm count, and increased deformity rate in male mice. These findings provide experimental evidence supporting their potential application in animal immunocastration. Full article
(This article belongs to the Section Veterinary Vaccines)
Show Figures

Figure 1

15 pages, 3554 KiB  
Article
A Composite Substrate of Ag Nanoparticle-Decorated Inverse Opal Polydimethylsiloxane for Surface Raman Fluorescence Dual Enhancement
by Zilun Tang, Hongping Liang, Zhangyang Chen, Jianpeng Li, Jianyu Wu, Xianfeng Li and Dingshu Xiao
Polymers 2025, 17(14), 1995; https://doi.org/10.3390/polym17141995 - 21 Jul 2025
Viewed by 330
Abstract
It is difficult to simultaneously achieve surface-enhanced Raman scattering (SERS) and surface-enhanced fluorescence (SEF) for noble metals. Herein, a composite substrate is demonstrated based on the rational construction of Ag nanoparticles (Ag NPs) and inverse opal polydimethylsiloxane (PDMS) for surface Raman fluorescence dual [...] Read more.
It is difficult to simultaneously achieve surface-enhanced Raman scattering (SERS) and surface-enhanced fluorescence (SEF) for noble metals. Herein, a composite substrate is demonstrated based on the rational construction of Ag nanoparticles (Ag NPs) and inverse opal polydimethylsiloxane (PDMS) for surface Raman fluorescence dual enhancement. The well-designed Ag nanoparticle (Ag NP)-decorated inverse opal PDMS (AIOP) composite substrate is fabricated using the polystyrene (PS) photonic crystal method and the sensitization reduction technique. The inverse opal PDMS enhances the electromagnetic (EM) field by increasing the loading of Ag NPs and plasmonic coupling of Ag NPs, leading to SERS activity. The thin shell layer of polyvinyl pyrrolidone (PVP) in core–shell Ag NPs isolates the detected molecule from the Ag core to prevent the fluorescence resonance energy transfer and charge transfer to eliminate fluorescence quenching and enable SEF performance. Based on the blockage of the core–shell structure and the enhanced EM field originating from the inverse opal structure, the as-fabricated AIOP composite substrate shows dual enhancement in surface Raman fluorescence. The AIOP composite substrate in this work, which combines improved SERS activity and SEF performance, not only promotes the development of surface-enhanced spectroscopy but also shows promise for applications in flexible sensors. Full article
(This article belongs to the Special Issue Polymer-Based Flexible Materials, 3rd Edition)
Show Figures

Figure 1

19 pages, 3119 KiB  
Article
Aquathermolytic Upgrading of Zarafshanian Extra Heavy Oil Using Ammonium Alum
by Amirjon Ali Akhunov, Firdavs Aliev, Nurali Mukhamadiev, Oscar Facknwie Kahwir, Alexey Dengaev, Mohammed Yasin Majeed, Mustafa Esmaeel, Abdulvahhab Al-Qaz, Oybek Mirzaev and Alexey Vakhin
Molecules 2025, 30(14), 3013; https://doi.org/10.3390/molecules30143013 - 18 Jul 2025
Viewed by 330
Abstract
The growing global demand for energy necessitates the efficient utilization of unconventional petroleum resources, particularly heavy oil reserves. However, extracting, transporting, and processing these resources remain challenging due to their low mobility, low API gravity, and significant concentrations of resins, asphaltenes, heteroatoms, and [...] Read more.
The growing global demand for energy necessitates the efficient utilization of unconventional petroleum resources, particularly heavy oil reserves. However, extracting, transporting, and processing these resources remain challenging due to their low mobility, low API gravity, and significant concentrations of resins, asphaltenes, heteroatoms, and metals. In recent years, various in situ upgrading techniques have been explored to enhance heavy oil quality, with catalytic aquathermolysis emerging as a promising approach. The effectiveness of this process largely depends on the development of cost-effective, environmentally friendly catalysts. This study investigates the upgrading performance of water-soluble ammonium alum, (NH4)Al(SO4)2·12H2O, for an extra-heavy oil sample from the Zarafshan Depression, located along the Tajikistan–Uzbekistan border. Comprehensive analyses demonstrate that the catalyst facilitates the breakdown of heavy oil components, particularly resins and asphaltenes, into lighter fractions. As a result, oil viscosity was significantly reduced by 94%, while sulfur content decreased from 896 ppm to 312 ppm. Furthermore, thermogravimetric (TG-DTG) analysis, coupled with Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD), revealed that the thermal decomposition of ammonium alum produces catalytically active Al2O3 nanoparticles. These findings suggest that ammonium alum is a highly effective water-soluble pre-catalyst for hydrothermal upgrading, offering a viable and sustainable solution for the development of extra-heavy oil fields. Full article
Show Figures

Figure 1

24 pages, 10648 KiB  
Article
Green-Synthesized Silver Nanoparticle-Loaded Antimicrobial Films: Preparation, Characterization, and Food Preservation
by Wenxi Yu, Qin Lei, Jingxian Jiang, Jianwei Yan, Xijian Yi, Juan Cheng, Siyu Ou, Wenjia Yin, Ziyan Li and Yuru Liao
Foods 2025, 14(14), 2509; https://doi.org/10.3390/foods14142509 - 17 Jul 2025
Viewed by 390
Abstract
This study presented a novel antimicrobial packaging PVA/xanthan gum film decorated with green-synthesized silver nanoparticles (AgNPs) derived from Myrica rubra leaf extract (MRLE) for the first time. Montmorillonite (MMT) was used to improve its dispersion (AgNPs@MMT). The synthesis time, temperature, and [...] Read more.
This study presented a novel antimicrobial packaging PVA/xanthan gum film decorated with green-synthesized silver nanoparticles (AgNPs) derived from Myrica rubra leaf extract (MRLE) for the first time. Montmorillonite (MMT) was used to improve its dispersion (AgNPs@MMT). The synthesis time, temperature, and concentration of AgNO3 were considered using a central composite design coupled with response surface methodology to obtain the optimum AgNPs (2 h, 75 °C, 2 mM). Analysis of substance concentration changes confirmed that the higher phenolic and flavonoid content in MRLE acted as reducing agents and stabilizers in AgNP synthesis, participating in the reaction rather than adsorbing to nanoparticles. TEM, XRD, and FTIR images revealed a spherical shape of the prepared AgNPs, with an average diameter of 8.23 ± 4.27 nm. The incorporation of AgNPs@MMT significantly enhanced the mechanical properties of the films, with the elongation at break and shear strength increasing by 65.19% and 52.10%, respectively, for the PAM2 sample. The films exhibited strong antimicrobial activity against both Escherichia coli (18.56 mm) and Staphylococcus aureus (20.73 mm). The films demonstrated effective food preservation capabilities, significantly reducing weight loss and extending the shelf life of packaged grapes and bananas. Molecular dynamics simulations reveal the diffusion behavior of AgNPs in different matrices, while the measured silver migration (0.25 ± 0.03 mg/kg) complied with EFSA regulations (10 mg/kg), confirming its food safety. These results demonstrate the film’s potential as an active packaging material for fruit preservation. Full article
Show Figures

Figure 1

20 pages, 2612 KiB  
Article
Development and Evaluation of a Nanoparticle-Based Immunoassay for Rotavirus Detection: A Suitable Alternative to ELISA and PCR in Low-Income Setting
by Margaret Oluwatoyin Japhet, Adeogo Timilehin Bankole, Temiloluwa Ifeoluwa Omotade, Oyelola Eyinade Adeoye, Oladiran Famurewa and Simeon K. Adesina
Methods Protoc. 2025, 8(4), 81; https://doi.org/10.3390/mps8040081 - 17 Jul 2025
Viewed by 386
Abstract
Every year, diarrhoea is responsible for >1 million deaths in children with ages from 0 to 5 years, with rotavirus as the leading cause. The regions most affected lack routine rotavirus diagnosis due to high cost, lack of necessary equipment and shortage of [...] Read more.
Every year, diarrhoea is responsible for >1 million deaths in children with ages from 0 to 5 years, with rotavirus as the leading cause. The regions most affected lack routine rotavirus diagnosis due to high cost, lack of necessary equipment and shortage of trained-personnel for Enzyme-Link-Immunosorbent-Assay (ELISA) and molecular methods. We report the development and evaluation of a cheap, nanoparticle-based immunoassay for routine machine-free rotavirus diagnosis. In this work, optimal conditions for oxidation of cotton swabs and aldehyde production for kit development was confirmed by Fourier-Transform Infrared Spectroscopy (FTIR). Lactoferrin (LF) needed to bind the virus to the cotton swab was immobilised on activated cotton swabs, followed by the capture of commercial rotavirus antigen on LF-immobilised swabs. This was dipped in coloured nanobeads covalently coupled to rotavirus-group-specific monoclonal antibody for visual rotavirus detection. Subsequently, rotavirus detection by nanoassay, commercial ELISA and quantitative reverse transcription PCR were compared using same set of 186 stool samples and subjected to statistical analyses. Optimal oxidisation condition was observed using 48 mg/mL NaIO4 in 0.1 M sodium acetate buffer at 35 °C for 9 h. Rotavirus detection was confirmed visually by blue colour retention on swabs after several washings. Sensitivity, specificity, positive-predictive-value and negative-predictive-value of ELISA in rotavirus detection were 60%, 84%, 53% and 88%, respectively, while our immunoassay showed performance at 88%, 94%, 82% and 96%. This immunoassay will provide effective rotavirus public health interventions in low-and-middle-income countries with high morbidity/mortality. Full article
(This article belongs to the Section Biochemical and Chemical Analysis & Synthesis)
Show Figures

Figure 1

23 pages, 13783 KiB  
Article
Synthesis and Characterization of a Nanocomposite Based on Opuntia ficus indica for Efficient Removal of Methylene Blue Dye: Adsorption Kinetics and Optimization by Response Surface Methodology
by Yasser Boumezough, Gianluca Viscusi, Sihem Arris, Giuliana Gorrasi and Sónia A. C. Carabineiro
Int. J. Mol. Sci. 2025, 26(14), 6717; https://doi.org/10.3390/ijms26146717 - 13 Jul 2025
Viewed by 355
Abstract
In this study, an efficient and cost-effective nanocomposite material based on Opuntia ficus indica (cactus) powder modified with iron oxide nanoparticles was developed as an adsorbent for the removal of methylene blue (MB), a common water pollutant. The nanocomposite was synthesized through the [...] Read more.
In this study, an efficient and cost-effective nanocomposite material based on Opuntia ficus indica (cactus) powder modified with iron oxide nanoparticles was developed as an adsorbent for the removal of methylene blue (MB), a common water pollutant. The nanocomposite was synthesized through the co-precipitation method of Fe2+ and Fe3+ ions and characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS) and thermogravimetric analysis (TGA). Batch adsorption experiments were conducted over 24 h, varying different operational conditions, such as pH, temperature and initial pollutant concentration. Furthermore, a Box–Behnken design was employed to develop an empirical model for predicting removal efficiency and optimizing the adsorption conditions. The effects of adsorption variables including contact time (1–60 min), initial MB concentration (20–100 mg/L), pH (2–12), adsorbent dosage (2–6 g/L) and temperature (25–55 °C) on the removal capacity were examined. Under optimal conditions, the maximum removal efficiency of MB reached approximately 96%, with a maximum adsorption capacity of 174 mg/g, as predicted by the Langmuir model. The synthesized cactus/iron oxide nanocomposite demonstrated significant potential as an adsorbent for treating MB-contaminated water. Full article
(This article belongs to the Special Issue Molecular Research and Applications of Nanomaterials)
Show Figures

Figure 1

19 pages, 2490 KiB  
Article
Linker-Free Hyaluronic Acid-Dexamethasone Conjugates: pH-Responsive Nanocarriers for Targeted Anti-Inflammatory Therapy
by Anton N. Bokatyi, Natallia V. Dubashynskaya, Igor V. Kudryavtsev, Andrey S. Trulioff, Artem A. Rubinstein, Elena N. Vlasova and Yury A. Skorik
Int. J. Mol. Sci. 2025, 26(14), 6608; https://doi.org/10.3390/ijms26146608 - 10 Jul 2025
Viewed by 616
Abstract
The covalent conjugation of pharmaceutical compounds to polymeric carriers represents an effective strategy for enhancing drug properties, including improved bioavailability, targeted delivery, and sustained release, while reducing systemic toxicity and adverse effects. By exploiting the physicochemical characteristics of biopolymers—particularly molecular charge and weight—we [...] Read more.
The covalent conjugation of pharmaceutical compounds to polymeric carriers represents an effective strategy for enhancing drug properties, including improved bioavailability, targeted delivery, and sustained release, while reducing systemic toxicity and adverse effects. By exploiting the physicochemical characteristics of biopolymers—particularly molecular charge and weight—we engineered a polymeric platform for glucocorticoid delivery with precisely controlled parameters including particle size, surface charge, targeting capability, and release kinetics. This study reports a linker-free synthesis of hyaluronic acid-dexamethasone (HA-DEX) conjugates through Steglich esterification, catalyzed by 4-dimethylaminopyridine (DMAP), which facilitates the acylation of sterically hindered alcohols. The reaction specifically couples carboxyl groups of hyaluronic acid with the C21 hydroxyl group of dexamethasone. Incorporation of hydrophobic dexamethasone moieties induced self-assembly into nanoparticles featuring a hydrophobic core and negatively charged hydrophilic shell (−20 to −25 mV ζ-potential). In vitro characterization revealed pH-dependent release profiles, with 80–90% dexamethasone liberated in mildly acidic phosphate buffer (pH 5.2) versus 50–60% in phosphate-buffered saline (pH 7.4) over 35 days, demonstrating both sustained release and inflammation-responsive behavior. The conjugates exhibited potent anti-inflammatory activity in a human tumor necrosis factor-α (TNFα)-induced inflammation model. These findings position HA-DEX conjugates as promising candidates for targeted glucocorticoid delivery to specific anatomical sites including ocular, articular, and tympanic tissues, where their combination of CD44-targeting capability, enhanced permeability and retention effects, and stimulus-responsive release can optimize therapeutic outcomes while minimizing off-target effects. Full article
(This article belongs to the Section Macromolecules)
Show Figures

Figure 1

19 pages, 5895 KiB  
Article
Receptor-Mediated SPION Labeling of CD4+ T Cells for Longitudinal MRI Tracking of Distribution Following Systemic Injection in Mouse
by Yu Ping, Songyue Han, Brock Howerton, Francesc Marti, Jake Weeks, Roberto Gedaly, Reuben Adatorwovor and Fanny Chapelin
Nanomaterials 2025, 15(14), 1068; https://doi.org/10.3390/nano15141068 - 10 Jul 2025
Viewed by 491
Abstract
Tracking T cells in vivo using MRI is a major challenge due to the difficulty of labeling these non-phagocytic cells with a sufficient contrast agent to generate a detectable signal change. In this study, we explored CD4-Superparamagnetic iron oxide nanoparticles (SPION), which is [...] Read more.
Tracking T cells in vivo using MRI is a major challenge due to the difficulty of labeling these non-phagocytic cells with a sufficient contrast agent to generate a detectable signal change. In this study, we explored CD4-Superparamagnetic iron oxide nanoparticles (SPION), which is commonly used in magnetic cell sorting, as a potential receptor-mediated, specific CD4+ T cell MRI labeling agent. We optimized the labeling protocol for maximal CD4+ cell labeling and viability. Cell health was confirmed with trypan blue assay, and labeling efficacy was confirmed with Prussian blue staining, transmission electron microscopy, and MRI of labeled cell pellets. Key cell functionality was assessed by flow cytometry. Next, CD4-SPION-labeled T cells or unlabeled T cells were delivered via intravenous injection in naïve mice. Liver MRIs pre-, 24 h, and 72 h post-T cell injection were performed to determine in vivo tracking ability. Our results show that CD4-SPION induces significant attenuation of T2 signals in a concentration-dependent manner, confirming their potential as an effective MRI contrast agent. In vitro, analyses showed that CD4+ T cells were able to uptake CD4-SPION without affecting cellular activity and key functions, as evidenced by Prussian blue staining and flow cytometric analysis of IL-2 receptor and the IL-7 receptor α-chains, CD69 upregulation, and IFN-γ secretion. In vivo, systemically distributed CD4-SPION-labeled T cells could be tracked in the liver at 24 and 72 h after injection, contrary to controls. Histological staining of tissue sections validated the findings. Our results showed that SPION CD4+ T cell sorting coupled with longitudinal MR imaging is a valid method to track CD4+ T cells in vivo. This safe, specific, and sensitive approach will facilitate the use of SPION as an MRI contrast agent in clinical practice, allowing for non-invasive tracking of adoptive cell therapies in multiple disease conditions. Full article
Show Figures

Figure 1

22 pages, 3291 KiB  
Article
Matrix Interference Removal Using Fe3O4@SiO2-PSA-Based Magnetic Dispersive Solid-Phase Extraction for UPLC-MS/MS Analysis of Diazepam in Aquatic Products
by Mengqiong Yang, Guangming Mei, Daoxiang Huang, Xiaojun Zhang, Pengfei He and Si Chen
Foods 2025, 14(14), 2421; https://doi.org/10.3390/foods14142421 - 9 Jul 2025
Viewed by 301
Abstract
A sensitive method was developed for detecting diazepam residues in aquatic products using magnetic dispersive solid-phase extraction (MDSPE) coupled with ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). Samples extracted with 1% ammonia–acetonitrile were purified using synthesized Fe3O4@SiO2-PSA nanoparticles [...] Read more.
A sensitive method was developed for detecting diazepam residues in aquatic products using magnetic dispersive solid-phase extraction (MDSPE) coupled with ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). Samples extracted with 1% ammonia–acetonitrile were purified using synthesized Fe3O4@SiO2-PSA nanoparticles via MDSPE before UPLC-MS/MS analysis. Separation was performed on a C18 column with gradient elution using 0.1% formic acid–2 mM ammonium acetate/methanol. Detection employed positive electrospray ionization (ESI+) in multiple reaction monitoring (MRM) mode. Characterization confirmed Fe3O4@SiO2-PSA’s mesoporous structure with excellent adsorption capacity and magnetic properties. The method showed good linearity (0.1–10 μg/L, r > 0.99) with an LOD and LOQ of 0.20 μg/kg and 0.50 μg/kg, respectively. Recoveries at 0.5–15.0 µg/kg spiking levels were 74.9–109% (RSDs 1.24–11.6%). This approach provides rapid, accurate, and high-precision analysis of diazepam in aquatic products, meeting regulatory requirements. Full article
Show Figures

Figure 1

11 pages, 11723 KiB  
Article
Spectrally Resolved Dynamics of Delayed Luminescence in Dense Scattering Media
by Mahshid Zoghi, Ernesto Jimenez-Villar and Aristide Dogariu
Materials 2025, 18(13), 3194; https://doi.org/10.3390/ma18133194 - 6 Jul 2025
Viewed by 347
Abstract
Highly scattering media have garnered significant interest in recent years, ranging from potential applications in solar cells, photocatalysis, and other novel photonic devices to research on fundamental topics such as topological photonics, enhanced light–matter coupling and light confinement. Here, we report measurements of [...] Read more.
Highly scattering media have garnered significant interest in recent years, ranging from potential applications in solar cells, photocatalysis, and other novel photonic devices to research on fundamental topics such as topological photonics, enhanced light–matter coupling and light confinement. Here, we report measurements of spectrally and time-resolved delayed luminescence (DL) in highly scattering rutile TiO2 films. The complex emission kinetics manifests in the non-exponential decay of photon density and the temporal evolution of the spectral composition. We found that while the energy levels of TiO2 nanoparticles broadly set the spectral regions of excitation and emission, our results demonstrate that the DL intensity and duration are strongly influenced by the inherent multiple elastic and inelastic processes determined by the mesoscale inhomogeneous structure of random media. We show that the lifetime of DL increases up to 6 s for the largest redshift detected, which is associated with multiple reabsorption processes. We outline a simple model for spectrally resolved DL emission from dense scattering media that can guide the design and characterization of composite materials with specific spectral and temporal properties. Full article
(This article belongs to the Section Smart Materials)
Show Figures

Figure 1

Back to TopTop