Search Results (184)

Nanotechnology has significantly advanced cancer therapy, particularly through the development of multifunctional nanoparticles (NPs) capable of acting as both therapeutic and diagnostic agents. This review focuses on the synergistic integration of radiotherapy (RT) and photothermal therapy (PTT) mediated by engineered NPs—a rapidly evolving strategy that enhances tumor specificity, minimizes healthy tissue damage, and enables real-time imaging. By analyzing the recent literature, we highlight the dual role of NPs in amplifying radiation-induced DNA damage and converting near-infrared (NIR) light into localized thermal energy. The review classifies various metal-based and composite nanomaterials (e.g., Au, Pt, Bi, Cu, and Fe) and evaluates their performance in preclinical RT–PTT settings. We also discuss the physicochemical properties, targeting strategies, and theragnostic applications that contribute to treatment efficiency. Unlike conventional combinatorial therapies, NP-mediated RT–PTT enables high spatial–temporal control, immunogenic potential, and integration with multimodal imaging. We conclude with the current challenges, translational barriers, and outlooks for clinical implementation. This work provides a comprehensive, up-to-date synthesis of NP-assisted RT–PTT as a powerful approach within the emerging field of nano-oncology. Full article

Multidrug-resistant (MDR) biofilm infections characterized by densely packed microbial communities encased in protective extracellular matrices pose a formidable challenge to conventional antimicrobial therapies and are a major contributor to chronic, recurrent and device-associated infections. These biofilms significantly reduce antibiotic penetration, facilitate the survival of dormant persister cells and promote horizontal gene transfer, all of which contribute to the emergence and persistence of MDR pathogens. Metal nanoparticles (MNPs) have emerged as promising alternatives due to their potent antibiofilm properties. However, conventional synthesis methods are associated with high costs, complexity, inefficiency and negative environmental impacts. To overcome these limitations there has been a global push toward the development of sustainable and eco-friendly synthesis approaches. Recent advancements have demonstrated the successful use of various plant extracts, microbial cultures, and biomolecules for the green synthesis of MNPs, which offers biocompatibility, scalability, and environmental safety. This review provides a comprehensive overview of recent trends and the latest progress in the green synthesis of MNPs including silver (Ag), gold (Au), platinum (Pt), and selenium (Se), and also explores the mechanistic pathways and characterization techniques. Furthermore, it highlights the antibiofilm applications of these MNPs emphasizing their roles in disrupting biofilms and restoring the efficacy of existing antimicrobial strategies. Full article

The development of metal–organic framework (MOF)-based composites for photocatalytic hydrogen evolution has garnered significant attention due to their tunable structures, high surface area, and abundant active sites. Recent advancements focus on enhancing light absorption, charge separation, and catalytic efficiency through strategies such as ligand functionalization, metal doping, heterojunction formation, and plasmonic coupling effects. For instance, modifications with Ir (III) complexes and Pt nanoparticles have significantly improved hydrogen evolution rates, while sandwich-structured MOF composites demonstrate optimized charge separation through tailored micro-environments and proton reduction efficiency. Additionally, integrating MOFs with semiconductors (e.g., CdS, g-C₃N₄) or plasmonic metals (e.g., Au) enhances visible-light responsiveness and stability. This review highlights key design principles, performance metrics, and mechanistic insights, providing a roadmap for future research in MOF-based photocatalysts for sustainable hydrogen production. Challenges such as long-term stability and scalable synthesis are also discussed to guide further innovations in this field. Full article

This study examines the impact of Au nanoparticles (Au-NPs) on the chemoresistive gas sensing properties as a function of particle size. The sensing material is composed of ultrathin CuO/Cu₂O films, which are fabricated by either thermal deposition technology or spray pyrolysis. These are used on a silicon nitride (Si₃N₄) micro hotplate (µh) chip with Pt electrodes and heaters. The gas sensing material is then functionalised with Au-NP of varying sizes (12, 20, and 40 nm, checked by transmission electron microscopy) using drop coating technology. The finalised sensors are tested by measuring the electrical resistance against various target gases, including carbon monoxide (CO), carbon dioxide (CO₂), and a mixture of hydrocarbons (HC_Mix), in order to evaluate any cross-sensitivity issues. While the sensor response is markedly contingent on the structural surface, our findings indicate that the dimensions of the Au-NPs exert a discernible influence on the sensor’s behaviour in response to varying target gases. The 50 nm thermally evaporated CuO/Cu₂O layers exhibited the highest sensor response of 78% against 2000 ppm CO₂. In order to gain further insight into the surface of the sensors, a scanning electron microscope (SEM) was employed, and to gain information about the composition, Raman spectroscopy was also utilised. Full article

Bacterial infections are the primary cause of mastitis in dairy cattle. Fungal mastitis occurs in 1–12% of cases. Antibiotic therapy, the standard treatment for mastitis, has led to antibiotic-resistant bacteria, reducing treatment efficacy and increasing fungal mastitis occurrence. Antibiotics lack biocidal effects on fungi, which often exhibit resistance to antifungal agents. This study evaluated the antifungal properties of nanoparticles (NPs) against Candida albicans, Candida glabrata, Candida parapsilosis, Diutina rugosa var. rugosa, Diutina catenulata, and Diutina rugosa. Tested NPs included gold (AuNPs), silver (AgNPs), copper (CuNPs), iron with hydrophilic carbon coating (FeCNPs) (1.56–25 mg/L), and platinum (PtNPs) (0.625–10 mg/L), along with their complexes. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) at 0.75–25 mg/L for AuNPs, AgNPs, CuNPs, and FeCNPs and 0.313–10 mg/L for PtNPs, as well as fungal sensitivity to standard antifungals, were determined. Each strain showed different sensitivities depending on the NPs used and their concentrations. C. glabrata was the most resistant to nanoparticles, while D. catenulata was the most susceptible. PtNPs and FeCNPs showed no or weak biocidal properties. Some mycotic-resistant strains were sensitive to nanoparticles. This study indicates a high in vitro antifungal potential for the application of nanoparticles, especially AgCuNPs, as a new effective non-antibiotic agent for the prevention and control of mycotic mastitis in dairy cattle. Full article

Gold nanostars (AuNSTs) stabilized with adenosine monophosphate (AMP) were synthesized using a scalable method, achieving a 30-fold yield increase compared to previous studies using AMP as a shaping agent, while also reducing the reaction time to 3 h. The AuNSTs were coated with mesoporous silica (mSiO₂) via a robust approach, producing the AuNSTs@mSiO₂ nanoparticles (NPs) with tunable thicknesses and consistent optical properties for a range of morphologies. The NPs were additionally coated with platinum (Pt) before synthesizing the mSiO₂ layer, facilitating a comparative analysis of catalytic activity. The catalytic performance of the bare AuNSTs, the AuNSTs@mSiO₂, and the AuNSTs@Pt@mSiO₂ was evaluated through methylene blue reduction, confirming the gold core as the primary catalytic source. The AuNSTs@Pt@mSiO₂ exhibited enhanced activity, highlighting the potential of the mSiO₂ coatings. Additionally, solid-phase catalytic tests using 3,3′,5,5′-tetramethylbenzidine (TMB) on cellulose discs demonstrated the effectiveness of these NPs under diverse conditions. These findings showcase the versatility and broad catalytic potential of silica-coated NPs for solution- and solid-phase applications. Full article

Background/Objectives: Bacterial infections remain among the top ten major public health concerns, contributing to a high number of incidences of disease and mortality worldwide, exacerbated by the rise of multidrug-resistant bacteria (MDRB). Consequently, it is crucial to develop novel antimicrobial strategies, including the use of functional nanoparticles. Gold nanoparticles (GNPs) have emerged as promising candidates due to their unique optical properties, particularly their ability to efficiently convert absorbed light into heat through the photothermal (PT) effect, which can be harnessed for bacteria eradication. Methods: Chitosan was modified with 3-mercaptopropionic acid to introduce sulfur groups, facilitating gold deposition onto chitosan nanoparticle (TCNPs) surface. The gold shell was subsequently formed via a seed-mediated method, wherein gold seeds were adsorbed onto TCNPs and further grown to form the shell. Photothermal effect on the bacterial viability was evaluated. Results: TCNPs with a size of 178 nm and spherical morphology were obtained. After the gold shell (TCNP@Au) exhibited a photothermal conversion efficiency of 31%, making them a promising photothermal agent for bacterial clearance. Notably, the viability of Escherichia coli was significantly reduced in the presence of TCNP@Au and was almost eradicated upon PT treatment. In contrast, TCNP@Aus were non-toxic for Staphylococcus aureus. Conclusions: TCNP@Au demonstrated favorable photothermal properties, presenting a novel nanoplatform for antibacterial applications, particularly against Gram-negative bacteria. However, further investigation is required to optimize the PT-based strategies against Gram-positive bacteria, such as S. aureus. Full article

Amperometric biosensors (ABSs) and enzymatic biofuel cells (BFCs) share several fundamental principles in their functionality, despite serving different primary purposes. Both devices rely on biorecognition, redox reactions, electron transfer (ET), and advanced electrode materials, including innovative nanomaterials (NMs). ABSs and BFCs, utilizing microbial oxidoreductases in combination with electroactive NMs, are both efficient and cost-effective. In the current study, several laboratory prototypes of BFCs have been developed with bioanodes based on yeast flavocytochrome b₂ (Fcb₂) and alcohol oxidase (AO), and a cathode based on fungal laccase. For the first time, BFCs have been developed featuring anodes based on Fcb₂ co-immobilized with redox NMs on a glassy carbon electrode (GCE), and cathode-utilizing laccase combined with gold–cerium–platinum nanoparticles (nAuCePt). The most effective lactate BFC, which contains gold–hexacyanoferrate (AuHCF), exhibited a specific power density of 1.8 µW/cm². A series of BFCs were developed with an AO-containing anode and a laccase/nAuCePt/GCE cathode. The optimal configuration featured a bioanode architecture of AO/nCoPtCu/GCE, achieving a specific power density of 3.2 µW/cm². The constructed BFCs were tested using lactate-containing food product samples as fuels. Full article

Interleukin-12 (IL-12), a crucial biomarker for immune and inflammatory responses, plays a pivotal role in diagnosing and managing diverse pathological conditions. Although colorimetric enzyme-linked immunosorbent assays (CELISAs) have been extensively employed to detect IL-12 in biological samples, their sensitivity is inherently limited by the catalytic efficiency of enzyme labels, presenting substantial challenges in achieving ultrasensitive detection and enabling pre-symptomatic diagnosis of diseases. In this study, we address this limitation by developing a novel peroxidase nanozyme, featuring ultrathin Pt skins consisting of only ~4 atomic layers, coated on Au nanoparticles (denoted as Au@Pt_4LNPs). These Au@Pt_4LNPs exhibit remarkable catalytic performance, achieving a ~1063-fold enhancement in peroxidase-like activity compared to horseradish peroxidase (HRP), while minimizing Pt consumption, thereby improving Pt utilization efficiency and reducing costs. This advancement facilitates the construction of an ultrasensitive CELISA capable of detecting IL-12 at femtomolar concentrations. Using Au@Pt_4LNPs as the signal labels, the developed CELISA demonstrates a quantitative detection range from 0.1 to 100 pg mL⁻¹, with a limit of detection (LOD) as low as 0.084 pg mL⁻¹ (1.1 fM), offering ~10 times greater sensitivity than the HRP-based CELISA. This study highlights the potential of Au@Pt_4LNP nanozymes as advanced signal labels, opening new avenues for next-generation ultrasensitive bioassays. Full article

The extraction of metallic nanoparticles (MNPs) from waste electrical and electronic equipment (WEEE) has gained extensive attention from researchers for eco-friendly, reliable, and sustainable alternative protocol over the traditional linear economic approach (make-use-dispose) for boosting the circular economy. A plethora of MNPs including metals/metal oxide nanoparticles having a size dimension ranging from 1–100 nanometers (nm) have been extracted from these WEEE by using different chemical, physical, and biological methods. Recovery of certain precious MNPs can be achieved by dismantling and recycling electronic waste items in the form of gold (Au), platinum (Pt), zinc oxide (ZnO), silver (Ag), and copper oxide (CuO). These MNPs provide a huge range of applications such as antibacterial, therapeutic, target drug delivery, and biotechnological applications. This comprehensive review provides in-depth knowledge of the synthesis of MNPs using different techniques from WEEE and delves into their potential applications in biomedical fields with in-depth mechanisms. This article also discussed global challenges and opportunities in this area for adopting the concept of circular economy to conserve natural resources for future generations and hence create a greener environment and protect our planet. Full article

Exosomes are important biomarkers for liquid biopsy in early cancer screening which play important roles in many biological processes, including apoptosis, inflammatory response, and tumor metastasis. In this study, an electrochemical aptamer immunosensor based on Au/MXene and AuPtPdCu was constructed for the sensitive detection of colorectal cancer-derived exosomes. AuNPs were deposited in situ on the surface of MXenes as a sensing platform due to their large specific area, excellent conductivity, and higher number of active sites for aptamer immobilization. The aptamer CD63 immobilized on Au/MXene can specifically capture target exosomes. Therefore, the AuPtPdCu-Apt nanoprobe further enhanced the sensitivity and accuracy of the immunosensor. A low limit of detection of 19 particles μL⁻¹ was achieved in the linear range of 50 to 5 × 10⁴ particles μL⁻¹ under optimal conditions. The immunosensor developed herein showed satisfactory electrochemical stability and anti-interference ability for the detection of exosomes in real serum samples. Full article

(1) Context: Cancer is still a major problem worldwide, and traditional therapies like radiation and chemotherapy often fail to alleviate symptoms because of side effects, systemic toxicity, and mechanisms of resistance. Beneficial anticancer effects that spare healthy tissues are made possible by the distinctive redox characteristics of noble metal complexes, especially those containing palladium, gold, silver, and platinum. (2) Methods: The redox processes, molecular targets, and therapeutic uses of noble metal complexes in cancer have been the subject of much study over the last 20 years; novel approaches to ligand design, functionalization of nanoparticles, and tumor-specific drug delivery systems are highlighted. (3) Results: Recent developments include Pt(IV) prodrugs and terpyridine-modified Pt complexes for enhanced selectivity and decreased toxicity; platinum complexes, like cisplatin, trigger reactive oxygen species (ROS) production and DNA damage. Functionalized gold nanoparticles (AuNPs) improve targeted delivery and theranostic capabilities, while gold complexes, particularly Au(I) and Au(III), inhibit redox-sensitive processes such as thioredoxin reductase (TrxR). (4) Conclusions: Ag(I)-based compounds and nanoparticles (AgNPs) induce DNA damage and mitochondrial dysfunction by taking advantage of oxidative stress. As redox-based anticancer medicines, noble metal complexes have the ability to transform by taking advantage of certain biochemical features to treat cancer more effectively and selectively. Full article

Near-infrared light (NIR)-responsive metal-based nanoparticles (NPs) could be used for tumour therapy. We examined how platinum (Pt), gold (Au), and core-shell Pt-Au NPs affect the viability of human hepatocellular carcinoma (HCC) cell lines (Hep3B, HepG2, and Huh7D-12) alone and in combination with NIR exposure. In addition, the expression of immune checkpoint molecules (ICMs) on the tumour cells was analysed. We revealed that the cytotoxicity and programmed cell death induction of Au and Pt-Au NPs toward HCC cells could be enhanced by NIR with 960 nm in a different way. Pt-Au NPs were the only particles that resulted in an additional temperature increase of up to 2 °C after NIR. Regarding the tumour cell immune phenotype, not all of the cells experienced changes in immune phenotype. NIR itself was the trigger of the alterations, while the NPs did not significantly affect the expression of most of the examined ICMs, such as PD-L1, PD-L1, HVEM, CD70, ICOS-L, Ox40-L, and TNFRSF9. The combination of Pt-Au NPs with NIR resulted in the most prominent increase of ICMs in HepG2 cells. We conclude that the thermotherapeutic effect of Pt-Au NP application and NIR could be beneficial in multimodal therapy settings in liver cancer for selected patients. Full article

Metal–organic frameworks (MOFs) have emerged as versatile materials with remarkably high surface areas and tunable properties, attracting significant attention for various applications. In this work, the modification of a UiO-66 MOF with metal nanoparticles (NPs) is investigated for the purpose of enhancing its photocatalytic activity for CO₂ reduction to liquid fuels. Several NPs (Au, Cu, Ag, Pd, Pt, and Ni) were loaded into the UiO-66 framework and employed as photocatalysts. The synergistic effects of plasmonic resonance and MOF characteristics were investigated to improve photocatalytic performance. The synthesized materials were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), confirming the successful integration of metal NPs onto the UiO-66 framework. Morphological analysis revealed distinct distributions and sizes of NPs on the UiO-66 surface for different metals. Photocatalytic CO₂ reduction experiments demonstrated enhanced activity of plasmonic MOFs, yielding methanol and ethanol. The findings revealed by this study provide valuable insights into tailoring MOFs for improved photocatalytic applications through the incorporation of plasmonic metal nanoparticles. Full article

In this study, a simple and easy synthesis strategy to realize the modification of AuHgPt nanoalloy materials on the surface of ITO glass at room temperature is presented. Gold nanoparticles as templates were obtained by electrochemical deposition, mercury was introduced as an intermediate to form an amalgam, and then a galvanic replacement reaction was utilized to successfully prepare gold–mercury–platinum (AuHgPt) nanoalloys. The obtained alloys were characterized by scanning electron microscopy, UV–Vis spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction techniques. The electrochemical sensing performance of the AuHgPt-modified electrode for hydrogen peroxide was evaluated by cyclic voltammetry and chronoamperometry. Under light conditions, the AuHgPt-modified electrode exhibited a desirable current response in the detection of hydrogen peroxide due to the synergistic effect of the localized surface plasmon resonance effect inherent in gold nanoparticles, and this synergistic effect improved the sensitivity of hydrogen peroxide detection. Meanwhile, the AuHgPt-modified electrode also exhibited better stability and reproducibility, which makes the modified electrode have great potential for various applications in the field of electrochemical sensing. Full article