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Ultraviolet (UV) photodetectors play a crucial role in various applications, ranging from environmental monitoring to biomedical diagnostics. This paper presents the fabrication and characterization of a high-performance UV photodetector using hexagonal boron nitride (hBN) decorated with gold nanoparticles (AuNPs). The hBN flakes were mechanically exfoliated onto SiO2 substrates, and AuNPs were formed via thermal evaporation, resulting in the creation of a plasmonically active surface that enhanced light absorption and carrier dynamics. Raman spectroscopy, transmission electron microscopy, and electrical measurements were performed to comprehensively analyze the device structure and performance. The photodetector exhibited significantly improved photocurrent and responsivity under UV-B (306 nm) and UV-C (254 nm) illumination, with the responsivity reaching an increase of nearly two orders of magnitude compared to that of the pristine hBN device. These improvements are attributed to the synergistic effects of the wide bandgap of hBN and the localized surface plasmon resonance of the AuNPs. These findings demonstrate the potential of AuNP-decorated hBN for advanced UV photodetection applications and provide a pathway toward more efficient and miniaturized optoelectronic devices. [ABSTRACT FROM AUTHOR]

The widespread use of synthetic polymers in various industries has raised worldwide concerns regarding their ecological impact and effects on human health. As a result, biopolymers have emerged as a promising alternative. Among them, exopolysaccharides (EPSs) produced by microbes from terrestrial niches have been extensively studied. However, recent reports have indicated that microbes from marine environments can also produce unique EPSs that could serve as sustainable substitutes to meet the escalating demand for biopolymers. The present study, for the first time, reports EPS production from novel marine bacterium Algoriphagus sp. K5R for sustainable application development. Interestingly, physicochemical analyses suggest that EPS K5R is a high molecular weight (1190.63 kDa) heteropolysaccharide composed of galacturonic acid, glucose and mannose. To evaluate EPS production, growth and fermentation kinetics were performed, which revealed that it was a primary metabolite having a maximum production of 4.79 ± 0.57 g L−1 with 2% (w/v) glucose. Moreover, EPS K5R exhibits exceptional functional properties, namely high water‐holding capacity (720% ± 80.29%) and oil‐holding capacity (493.33% ± 49.74% for coconut oil and 533.32% ± 17.47% for olive oil), and non‐Newtonian pseudo‐plastic behavior which render it a promising candidate for application in the cosmetics and food industries. In fact, its anti‐oxidant capabilities make it an ideal biological reducing agent for metal nanoparticle synthesis. Overall, this study highlights the potential of marine EPSs for a diverse array of industrial applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Flavokavain B (FKB), a hepatotoxic chalcone from Piper methysticum (kava), has raised safety concerns due to its role in disrupting redox homeostasis and inducing apoptosis in hepatocytes. Conventional chromatographic methods for FKB detection, while sensitive, are costly and impractical for field applications. In this work, DNA aptamers were selected using the library-immobilized method and high-throughput sequencing. Three families of aptamers were obtained, and the best one named FKB-S showed a dissociation constant (KD) of 280 nM using microscale thermophoresis. To demonstrate its practical utility, a rapid and label-free colorimetric aptasensor was developed based on aptamer-induced gold nanoparticle aggregation. This assay achieved a detection limit of 150 nM (43.46 ng/mL) and provided results within 10 min. Compared to traditional chromatographic methods, the aptasensor offers a simple, cost-effective, and equipment-free approach for on-site FKB detection, making it a promising tool for the quality control and safety monitoring of kava-based products in diverse environments. [ABSTRACT FROM AUTHOR]

AbstractThis study examines heat transfer and nanofluid-enhanced blood flow behaviour in stenotic arteries under inflammatory conditions, addressing critical challenges in cardiovascular health. The blood, treated as a Newtonian fluid, is augmented with gold nanoparticles to improve thermal conductivity and support drug delivery applications. A hybrid methodology combining finite element method (FEM) for numerical modelling and artificial neural networks (ANN) for stability prediction provides a robust analytical framework. Parametric analysis reveals that increasing stenosis severity (60% to 80%) results in a 45% enhancement in heat transfer, demonstrating the efficacy of nanoparticle integration. The results show that the size of the vortices decreases due to the position changing of the upper stenoses, whereas it rises with increasing stenosis peak. Higher nanoparticle volume fraction (ϕ) amplifies momentum diffusion, resulting in larger vortices, while improved thermal conductivity enhances heat transfer. Inflammation significantly affects flow patterns and heat transport with important implications in treating cardiovascular disorders and biological applications. The regression analysis confirms a close match between predicted and target data, showcasing the robustness of the FEM-ANN hybrid approach for modelling biofluid systems. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (NPs) are promising for cancer therapy due to their versatile shapes, optical properties, adjustable sizes, and facile functionalization. However, their diverse physicochemical properties, complex in vivo environments, and cellular heterogeneity lead to markedly different interactions with cells, impacting reproducibility and application selection. To address this, we implemented a DNA barcoding system to label gold NPs with varying shapes, sizes, and surface modifications for tumor delivery optimization. Six NP species, comprising three shapes (sphere, rod, triangle) and two sizes (40 nm, 80 nm), were tagged with unique DNA barcodes. Barcodes demonstrated minimal detachment, no interference with cell interactions, and resistance to DNase digestion. Next‐generation sequencing revealed that sphere NPs exhibited poor in vitro uptake but superior in vivo tumor targeting, likely due to enhanced endothelial interactions and reduced macrophage clearance. Additionally, 80 nm nanotriangles displayed excellent tumor targeting both in vitro and in vivo. Supporting experiments validated these findings. To demonstrate practical utility, the NPs were applied in siRNA delivery and photothermal therapy in a breast tumor model. This study pioneers the integration of DNA barcoding with gold NPs to systematically explore shape, size, and surface modifications for in vivo delivery. [ABSTRACT FROM AUTHOR]

Biomacromolecules generally exist and function in aqueous media. Is it possible to estimate the state and properties of molecules in an initial three-dimensional colloidal solution based on the structure properties of biomolecules adsorbed on the two-dimensional surface? Using atomic force microscopy to study nanosized objects requires their immobilization on a surface. Particles undergoing Brownian motion in a solution significantly reduce their velocity near the surface and become completely immobilized upon drying. Using radial distribution function (RDF) methods, it is possible to obtain information about the presence of short-range or long-range order in the arrangement of immobilized colloidal particles. In this work, RDF is applied to immobilized gold nanoparticles (AuNPs) and horseradish peroxidase molecules on mica. It is shown that AuNPs maintain mobility on the mica surface when water is present. Upon immobilization, AuNPs organize into an amorphous structure exhibiting short-range order. Protein molecules are immobilized randomly, and their surface density is well described by the Poisson distribution. [ABSTRACT FROM AUTHOR]

Understanding the interaction of hemoglobin (Hb) with various nanomaterials and nanoparticles (NPs) is of considerable interest for the design of enhanced oxygen carriers for therapeutic applications. In this report, we undertake an iterative study of the role of the capping ligand in determining the nature of Hb binding to the surface of spherical gold nanoparticles (AuNPs, 5 nm diameter). We show that AuNPs capped with citrate and thioctic acid TA-SO3 ligands show robust assembly of Hb to the AuNP surface while NPs capped with TA-CL4 ligands (short, zwitterionic ligands) exhibit minimal assembly of Hb to the NP surface. Citrate on the AuNP facilitates the efficient assembly of Hb to the NP surface through the formation of an Au–S bond between Au and free thiols on cysteine residues. Conversely, TA-SO3-capped AuNPs mediate the electrostatic assembly of Hb to the ligand coating. Hb assembly on the citrate and TA-SO3 AuNPs significantly changes the AuNP physical properties (e.g., hydrodynamic diameter, surface charge, and colloidal stability). Hb assembly on the citrate-AuNPs alters its spectral properties, while Hb assembly to TA-SO3-AuNPs shows minimal changes in AuNP spectral properties. More importantly, Hb undergoes different degrees of spectral and interstitial structural alterations, including changes to the heme absorption peak and modification in the secondary structure, upon being assembled with the AuNP. Circular dichroism (CD) spectroscopy data confirms a significant (50%) loss of Hb α-helix structure when assembled on the citrate-AuNP compared with TA-SO3-AuNP. Our results demonstrate the important consideration that must be given to the ligand coating when interfacing Hb (and other proteins) with NP materials for bioconjugate formation. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is an important chemical widely used in the industry. Recently, insulating zirconia‐supported Au nanoparticles (NPs) prepared by a modified deposition precipitation method (Au/ZrO2‐MDP) have been reported to show catalytic activity for H2O2 production from aerated HCOOH aqueous solution much higher than Au/n‐type semiconducting metal oxides (Au/n‐MOs) prepared by the normal deposition precipitation method. In this study, we report that Au/yttria‐stabilized zirconia (Au/YSZ‐MDP) exhibits catalytic activity for the reaction far exceeding those of Au/n‐MOs and even Au/ZrO2‐MDP. Au/YSZ‐MDP yields H2O2 from the aerated 1.06 M HCOOH aqueous solution with an initial rate of 2.2 mmol h−1 gcat−1, and a turnover frequency (TOF) of 4.3 × 102 h−1 at 25 °C. X‐ray photoelectron and photoluminescence spectral data, in addition to the effect of YSZ surface modification with an aluminum oxide, indicate that the remarkable catalytic activity of Au/YSZ‐MDP is induced by the oxygen vacancies (Ov) and Ov‐derived Zr─OH groups on the YSZ surface in the vicinity of Au NPs. [ABSTRACT FROM AUTHOR]

This study describes the development of an optical-based surface plasmon resonance (SPR) aptasensor for the detection of cocaine. The aptasensor was prepared by first attaching gold nanoparticles to a clean SPR chip surface, followed by the addition of an aptamer to create a modified surface. This surface was characterized using contact angle and atomic force microscopy, revealing surface roughness values of 0.28 nm and 28.12 nm for the blank and modified surfaces, respectively. The detection of cocaine was carried out in the concentration range of 1 ng/mL to 1000 ng/mL, with a detection time of approximately 8 min and a cocaine limit of detection (LOD) of 0.43 ng/mL. Repeatability studies were conducted, and the stability of the signal response was examined at a concentration of 200 ng/mL. Adsorption isotherm models, including Scatchard, Langmuir, and Freundlich models, were calculated to assess the surface homogeneity of the SPR aptasensor chip, with the results indicating compatibility with the Langmuir isotherm model. [ABSTRACT FROM AUTHOR]

The coronavirus pandemic has highlighted the urgent need for rapid, sensitive, and accurate diagnostic tests to detect SARS-CoV-2, which causes COVID-19 disease. One promising approach is the use of aptamers, which are synthetic single-stranded DNA or RNA molecules possessing the ability to bind to specific targets with high affinity and specificity. In this study, we developed an aptamer-based electrochemical biosensor to detect the SARS-CoV-2 spike protein, a viral antigen commonly utilized in diagnostic assays in a sandwich assay. To fabricate the electrochemical biosensor, a capture aptamer was immobilized onto a gold electrode. The target protein was introduced with a secondary aptamer-conjugated gold nanoparticle (AuNP) to enhance the electrical signals. AuNPs were prepared by utilizing L-ascorbic acid or hyaluronic acid and were functionalized with a secondary aptamer. The secondary aptamer-conjugated AuNPs were first characterized to identify their physicochemical properties. The biosensor exhibited exceptional sensitivity and specificity, with a detection limit of 0.42 pg/mL, and showed no cross-reactivity with other respiratory viruses. The aptamer-based biosensor, coupled with secondary aptamer-conjugated gold nanoparticles, has significant potential as a rapid, cost-effective, and highly sensitive diagnostic tool for COVID-19, as well as for the detection of other infectious agents. [ABSTRACT FROM AUTHOR]

Youshuai Meng,1,* Chuan Chen,1,2,* Ronggui Lin,1,3,* Linlin Zheng,4 Yanying Fan,5 Mengdi Zhang,1 Ziqi Zhang,1 Han Shi,1,3 Xiaohan Zheng,1,3 Junyu Chen,1 Dezhao Chen,1,3 Tianhong Teng,1,3 Bing Chen1 1Key Laboratory of Nanomedical Technology (Education Department of Fujian Province), Department of Pharmaceutical Analysis, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, People’s Republic of China; 2Innovation Center for Enzyme Catalysis and Drug Synthesis, School of Pharmacy, Xiamen Medical College, Xiamen, 361023, People’s Republic of China; 3Department of General Surgery/ Department of Obstetrics & Gynecology, Fujian Medical University Union Hospital, Fuzhou, 350001, People’s Republic of China; 4Department of Oncology, Affiliated Hospital of Putian University, Putian, 351199, People’s Republic of China; 5Fuzhou Children’s Hospital of Fujian Province, Fuzhou, 350005, People’s Republic of China*These authors contributed equally to this workCorrespondence: Bing Chen, School of Pharmacy, Fujian Medical University, Fuzhou, 350122, People’s Republic of China, Email BingChen_001@126.com, BingChen_001@fjmu.edu.cn Tianhong Teng, Fujian Medical University Union Hospital, Fujian Medical University, Fuzhou, 350122, People’s Republic of China, Email tianhongteng24@fjmu.edu.cnBackground: The dense and fibrotic nature of the pancreatic tumor microenvironment significantly contributes to tumor invasion and metastasis. This challenging environment acts as a formidable barrier, hindering effective drug penetration and delivery, which ultimately limits the efficacy of conventional cancer treatments. Gold nanoparticles (AuNPs) have emerged as promising nanocarriers to overcome the extracellular matrix barrier; however, their limited targeting precision, poor delivery efficiency, and insufficient photothermal conversion present challenges.Methods: We developed triphenyl phosphonium-functionalized high-branch gold nanoparticles, denoted as Dox@TPAu, to enhance drug delivery and targeting capabilities. The targeted penetration, biopharmaceutical and pharmacokinetic properties of Dox@TPAu were characterized, and the synergistic therapeutic effect was evaluated by the BxPC-3 xenograft tumor mouse model.Results: Dox@TPAu exhibits superior photothermal conversion efficiency (91.0%) alongside a high drug loading efficiency (26%) and effective photo-triggered drug-release potential. This Dox@TPAu drug delivery system adeptly accumulates at tumor sites due to its unique properties, enabling targeted localization within cancer cells and the mitochondria of stromal fibroblasts. This localization disrupts mitochondrial function and transfer—processes crucial for energy production, metabolism, and cell signaling within the tumor microenvironment. Pharmacokinetic analyses revealed an optimal spatiotemporal distribution of Dox@TPAu at the tumor site. This strategic accumulation enables precise disruption of both the physical barrier and cancer cells, enhancing treatment efficacy through near-infrared light-triggered local chemo-photothermal synergistic therapy.Conclusion: Our findings demonstrate that this innovative strategy effectively leverages the unique properties of mitochondria-targeting, virus-like AuNPs for precise and efficient stromal depletion, presenting a promising approach to enhance the efficacy of pancreatic cancer treatment.Keywords: mitochondria-targeting, gold nanoparticle, stromal depletion, chemo-photothermal therapy, pancreatic cancer

The self-assembly of human islet amyloid polypeptide (hIAPP) monomers into oligomers and fibrils is linked to the development of type 2 diabetes (T2D). The initial oligomers formed during this process are known to contribute to cell death in T2D. Therefore, inhibiting and destabilizing these oligomers is considered a potential therapeutic strategy for T2D treatment. Epigallocatechin gallate (EGCG) is one of the small molecules known for its anti-aggregation activities. However, its clinical application against amyloid-related diseases is limited due to poor chemical stability and low bioavailability. To overcome these limitations, the conjugation of small molecules with nanoparticles has shown promising results. In this study, we explored the anti-aggregation properties of EGCG-functionalized gold nanoparticles (EGCG_AuNP) against hIAPP using all-atom molecular dynamics simulations. For comparison, we also studied hIAPP in isolation. Our findings revealed that the structural stability of hIAPP was significantly affected by the presence of EGCG_AuNP. Specifically, we observed reduced β-sheet conformations, increased solvent-accessible surface area (SASA), and reduced hydrogen bonds (H-bonds) when EGCG_AuNP interacted with hIAPP. This study highlights polyphenol-functionalized gold nanoparticles as a promising strategy for targeting protein aggregates associated with T2D. [ABSTRACT FROM AUTHOR]

Abstract The globalization of food distribution has made it necessary to ensure the delivery of fresh food to the consumers. Protein‐rich foods produce a significant amount of tyramine when spoiled. Therefore, it was envisaged to develop localized surface plasmon resonance (LSPR)—sensor for monitoring tyramine content in beef, mackerel, and cheese. For this purpose, the sensors were developed by coating the LSPR chip with gold nanoparticles (AuNPs) followed by conjugation of tyramine‐specific peptide (TYR1). The TYR1 was synthesized and screened by phage display and binding efficiency was evaluated by DockThor. The optimized LSPR sensor showed highest binding efficiency at TYR1 concentration of 20 µg/mL with reaction time of 40 min. The sensor also showed an excellent detection range for beef, mackerel, and cheese were 0.01–10 ppb, 0.01–10 ppm, and 0.01–10 ppb, respectively, in comparison to standard. These findings indicated that this sensor can be used as a promising tool for on‐site monitoring of food quality.

Abstract Metal and metal oxide nanocomposites have unique properties and are promising for antibacterial and anticancer applications. In this work, we aimed to highlight the relationship between the biosynthesis ways of silver and gold-doped zinc oxide nanocomposites and their functions as anticancer on cell lines (MCF-7 and HepG2). The propolis was used to biosynthesize four different nanoparticles with the same components, including zinc, gold and silver. The nanocomposites were characterized using various techniques, including ultraviolet–visible spectroscopy (UV–Vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy Dispersive X-ray analysis (EDX) and cytotoxicity assays. The result of this study showed that formed nanocomposites have a similar level of Zn, Au, and Ag, ranging from 23–34%, 2–6%, and 2–3%, respectively. In addition, adding the components simultaneously produces the fastest color change, and the fabricated nanoparticles have spherical shapes with different layers. In addition, the prepared nanoparticles influenced the cell viability of the cancer cell lines, with the most effective one when Zn, Au, and Ag were added spontaneously to form a nanocomposite called (All) with IC50 of 24.5 µg/mL for MCF7 cells and 29.1 µg/mL for HepG2 cells. Thus, the study illustrates that the preparation of nanocomposite generated through green synthesis with different methods significantly affects the structure and function and may improve the synthesis of nanocomposite to be developed into an efficacious therapeutic agent for cancers. In addition, this study opens the door toward a novel track in the field of nanocomposites as it links the synthesis with structure and function. Further anti-cancer properties, as well as animal testing are needed for those nanocomposites.

Melanoma is a type of skin cancer that can be challenging to treat, especially in advanced stages. Radiotherapy is one of the main treatment modalities for melanoma, but its efficacy can be limited due to the radioresistance of melanoma cells. Recently, there has been growing interest in using high-Z metal nanoparticles (NPs) to enhance the effectiveness of radiotherapy for melanoma. This review provides an overview of the current state of radiotherapy for melanoma and discusses the physical and biological mechanisms of radiosensitization through high-Z metal NPs. Additionally, it summarizes the latest research on using high-Z metal NPs to sensitize melanoma cells to radiation, both in vitro and in vivo. By examining the available evidence, this review aims to shed light on the potential of high-Z metal NPs in improving radiotherapy outcomes for patients with melanoma. Graphical Abstract Article highlights Melanoma, a lethal skin cancer from melanocytes, causes 75% of skin cancer-related deaths worldwide. Rising incidence necessitates urgent interventions. Traditional treatments like surgery, chemotherapy, immunotherapy and radiotherapy (RT) have limitations. Nanomedicine, using nanoparticles (NPs) sized 1–100 nm, shows promise in enhancing cancer treatment, especially high-Z metal NPs (e.g., gold, platinum, gadolinium) in improving RT outcomes for melanoma. Radiotherapy for melanoma RT is vital for melanoma management, especially when surgery is not viable or cancer has spread. Combining RT with immune checkpoint inhibitors (ICI) improves outcomes in brain metastases. Fractionated RT enhances T cell responses, similar to vaccines. Studies suggest higher radiation doses may be more effective, with clinical studies indicating a median total dose of 30 Gy and BED >39.0 Gy10. High-Z metal NPs can enhance RT by targeting cancer cells precisely while sparing healthy tissue. High-Z metal NPs for radiotherapy of melanoma High-Z metal NPs like gold, magnetic iron oxide, gadolinium, copper-cysteamine and platinum enhance RT efficacy while preserving healthy tissue. Gold NPs enhance RT through unique properties like surface plasmon resonance. mIONs offer RT combined with hyperthermia, enhancing therapeutic outcomes. Gadolinium enhances MRI and RT, with AGuIX® NPs allowing precise imaging and targeted therapy. Other high-Z metals like copper-cysteamine and platinum enhance ROS production, improving treatment outcomes. Nanoparticle physicochemistry & radiosensitization Key design factors include material, size, shape, surface coating and charge. NP size affects biodistribution and clearance, with optimal sizes for tumor uptake being 20–60 nm. NP concentration and surface charge impact RT enhancement and cytocompatibility. Synthesis methods, including chemical, physical and green, ensure biocompatibility and reduced toxicity. Coatings improve stability and targeting, essential for passive and active strategies, enhancing treatment efficacy. Mechanisms of High-Z Metal NPs radiosensitization Radiosensitization involves physical, chemical and biological phases. High-Z metal NPs enhance RT through the photoelectric effect and sary electron production, increasing local radiation doses. They modulate chemical reactions, enhancing DNA damage and ROS production. Biologically, NPs disrupt cell cycles, delay DNA repair and induce oxidative stress, increasing tumor cell radiosensitivity. Conclusion High-Z metal nanoparticles show significant promise in enhancing radiotherapy for melanoma. Benefits include efficient x-ray absorption, targeted delivery and induction of oxidative stress. Key challenges like ensuring biocompatibility, understanding mechanisms and optimizing NP design need addressing before clinical translation. Continued research is essential for developing effective and safe NP-based therapies. Future perspectives Future prospects include using NPs for targeted radiation doses to melanoma cells, optimizing delivery strategies and conducting preclinical and clinical studies to validate efficacy and safety. Continued innovations in nanomedicine could lead to more targeted, effective and personalized cancer treatments, transforming oncology. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (NPs) have demonstrated significance in several important fields, including drug delivery and anticancer research, due to their unique properties. Gold NPs possess significant optical characteristics that enhance their application in biosensor development for diagnosis, in photothermal and photodynamic therapies for anticancer treatment, and in targeted drug delivery and bioimaging. The broad surface modification possibilities of gold NPs have been utilized in the delivery of various molecules, including nucleic acids, drugs, and proteins. Moreover, gold NPs possess strong localized surface plasmon resonance (LSPR) properties, facilitating their use in surface-enhanced Raman scattering for precise and efficient biomolecule detection. These optical properties are extensively utilized in anticancer research. Both photothermal and photodynamic therapies show significant results in anticancer treatments using gold NPs. Additionally, the properties of gold NPs demonstrate potential in other biological areas, particularly in antimicrobial activity. In addition to delivering antigens, peptides, and antibiotics to enhance antimicrobial activity, gold NPs can penetrate cell membranes and induce apoptosis through various intracellular mechanisms. Among other types of metal NPs, gold NPs show more tolerable toxicity capacity, supporting their application in wide-ranging areas. Gold NPs hold a special position in nanomaterial research, offering limited toxicity and unique properties. This review aims to address recently highlighted applications and the current status of gold NP research and to discuss their future in nanomedicine. [ABSTRACT FROM AUTHOR]

Background: Salmonella, is one of the most important pathogens causing foodborne illnesses worldwide. The early detection of Salmonella is essential to minimize the risk. Herein, the nanoprobe (CS-AuNPs@phage-T156) for Salmonella was obtained by functionalizing cysteamine (CS) stabilized gold nanoparticles (CS-AuNPs) with phage T156. Results: In the presence of target Salmonella, the CS-AuNPs@phage-T156 specifically recognized and adsorbed on the surface of Salmonella, then induced the aggregation of gold nanoparticles and the color changes from red to purple, which enabled visual detection. The concentration of Salmonella was quantified by the absorption ratio (A680/A526), with a wide linear range from 1.2 × 101 CFU/mL to 1.2 × 106 CFU/mL. Under the optimal experimental conditions, this assay possessed a potent selectivity characteristic quickly toward Salmonella, with a detection limit of 12 CFU/mL. Conclusion: This simple and rapid detection method is expected to provides a novel identification element for the detection of Salmonella by intuitive visualization judgment and quantitative analysis. [ABSTRACT FROM AUTHOR]

The current study develops the first and novel gold nanoparticle‐ionic liquid nanostructure modified microbial biosensor based on Pleurotus ostreatus for the sensitive determination of Bisphenol A. In the construction of the microbial biosensor, lyophilized P.ostreatus cells were modified with ionic liquid‐cysteamine mixture on a gold electrode which was modified with 1,6‐hexanedithiol and gold nanoparticle. The measurement principle of the biosensor is based on the detection of changes in current in a phosphate buffer system (pH 7.5, 50 mM and containing 5.0 mM K3[Fe(CN)6]) in the potential range of −0.2 to +0.6 V depending on the BPA concentration. In the optimization studies of the microbial biosensor; the most suitable ionic liquid‐cysteamin ratio was 1 : 2 (v/v) and the incubation time of 1,6‐hexanedithiol on the gold electrode was 6 hours. Optimum working conditions were determined to be pH:7.5, 100 mM potassium phosphate buffer, and 35°C. In the characterization studies of the microbial biosensor, parameters such as linearity, interference effects of some substances on the microbial biosensor responses, repeatability, reproducibility and storage stability of the microbial biosensor were determined. The linear range of the biosensor was obtained 10–250 μM. Limit of detection was determined to be 1.57 μM and the response time was obtained 20 seconds. Real sample analysis was carried out by water samples that kept in plastic bottles for 6 months by using both the microbial biosensor and HPLC method. [ABSTRACT FROM AUTHOR]

Gold nanoparticles are extensively used across various industries, particularly in biomedical fields, due to their high biocompatibility, stability, and low toxicity. The rising use of gold nanoparticles in biomedical applications has increased the demand for more sustainable synthesis methods that reduce costs and environmental impacts compared to traditional chemical processes. This study presents a green synthesis approach utilizing leaf extracts from Pterospermum canescens and Vernonia elaeagnifolia. The synthesized nanoparticles were characterized using UV‐VIS, XRD, HRTEM‐SAED, FESEM‐EDX, XPS, and FTIR analyses. These characterizations confirmed the formation, size, shape, and morphological features of the nanoparticles, as well as the involvement of secondary plant metabolites in their synthesis. The nanoparticles were found to be less than 50 nm in size, with P.C AuNPs averaging 27.48 nm and V.E AuNPs averaging 14.79 nm. The particles predominantly exhibited spherical or distorted spherical shapes. In cytotoxicity assays using C6 rat glioma cells, both types of nanoparticles demonstrated significant effects. V.E AuNPs induced apoptosis in 78 % of the cells, while P.C AuNPs induced apoptosis in 50 %, confirming their cytotoxic efficacy. Gene expression studies further revealed that V.E AuNPs significantly upregulated caspase‐3 and downregulated BCL‐2, indicating a potent apoptotic response, while P.C AuNPs showed a similar but less pronounced effect. Additionally, in collagen‐induced platelet aggregation studies, V.E AuNPs exhibited substantial anti‐platelet activity with increasing dosages, reducing platelet aggregation to less than 10 % at a concentration of 30 μg/ml, compared to minimal inhibition by P.C AuNPs. Overall, the study demonstrates that gold nanoparticles synthesized from Vernonia elaeagnifolia and Pterospermum canescens are effective and offer promising applications in biomedicine. The results confirm the potential of these green‐synthesized nanoparticles for use in cancer treatment and sustainable anti‐platelet drug development [ABSTRACT FROM AUTHOR]