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Driven by their exceptional optical characteristics, robust chemical stability, and facile bioconjugation, gold nanoparticles (AuNPs) have emerged as a preferred material for detection and biosensing applications in scientific research. This study involves the development of a simple, rapid, and cost-effective colorimetric immuno-sensing probe to detect aflatoxin B1 and zearalenone using AuNP antibody (AuNP-mAb) conjugates. Anti-toxin antibodies were attached to the AuNPs by using the physical adsorption method. The colorimetric immunosensor developed operates on the principle that the optical properties of the AuNP are very sensitive to aggregation, which can be induced by a critical high salt concentration. Although the presence of antibodies on the AuNP surface inhibits the aggregation, these antibodies bind to the toxin with higher affinity, which leads to exposure of the surface of AuNPs and aggregation in a salt environment. The aggregation triggers a noticeable but variable alteration in color from red to purple and blueish gray, as a result of a red shift in the surface plasmon resonance band of the AuNPs. The extent of the shift is dependent on the toxin exposure dose and can be quantified using a calibration curve through UV–Visible–NIR spectroscopy. The limit of detection using this assay was determined to be as low as 0.15 ng/mL for both zearalenone and aflatoxin B1. The specificity of the prepared immunoprobe was analyzed for a particular mycotoxin in the presence of other mycotoxins. The developed immunoprobe was evaluated for real-world applicability using artificially spiked samples. This colorimetric immunoprobe based on localized surface plasmon resonance (LSPR) has a reduced detection limit compared to other immunoassays, a rapid readout, low cost, and facile fabrication. [ABSTRACT FROM AUTHOR]

Glioblastoma, an aggressive primary brain tumor, poses a significant challenge owing to its dynamic and intricate tumor microenvironment. This review investigates the innovative integration of biosensor-enhanced organ-on-a-chip (OOC) models as a novel strategy for an in-depth exploration of glioblastoma tumor microenvironment dynamics. In recent years, the transformative approach of incorporating biosensors into OOC platforms has enabled real-time monitoring and analysis of cellular behaviors within a controlled microenvironment. Conventional in vitro and in vivo models exhibit inherent limitations in accurately replicating the complex nature of glioblastoma progression. This review addresses the existing research gap by pioneering the integration of biosensor-enhanced OOC models, providing a comprehensive platform for investigating glioblastoma tumor microenvironment dynamics. The applications of this combined approach in studying glioblastoma dynamics are critically scrutinized, emphasizing its potential to bridge the gap between simplistic models and the intricate in vivo conditions. Furthermore, the article discusses the implications of biosensor-enhanced OOC models in elucidating the dynamic features of the tumor microenvironment, encompassing cell migration, proliferation, and interactions. By furnishing real-time insights, these models significantly contribute to unraveling the complex biology of glioblastoma, thereby influencing the development of more accurate diagnostic and therapeutic strategies. [ABSTRACT FROM AUTHOR]

The aim of this research is to define optimal conditions to improve the stability of gold and silver nanoparticles' anti-zearalenone antibody conjugates for their utilisation in lateral flow immunochromatographic assay (LFIA). The Turkevich–Frens method was used to synthesise gold nanoparticles (AuNPs), which were between 10 and 110 nm in diameter. Silver nanoparticles (AgNPs) with a size distribution of 2.5 to 100 nm were synthesised using sodium borohydride as a reducing agent. The onset of AuNP and AgNP aggregation occurred at 150 mM and 80 mM NaCl concentrations, respectively. Stable Au and Ag nanoparticle–antibody conjugates were achieved at 1.2 mM of K2CO3 concentration, which corresponds to the pH value of ≈7. Lastly, the highest degree of conjugation between Au and Ag nanoparticles and anti-zearalenone antibodies was at 4 and 6 µg/mL of antibody concentrations. The optimisation of the conjugation conditions can contribute to better stability of nanoparticles and their antibody conjugate and can improve the reproducibility of results of bioreporter molecules in biosensing lateral flow devices. [ABSTRACT FROM AUTHOR]

The detection of aflatoxins is essential for the food industry to ensure the safety and quality of food products before their release to the market. The lateral-flow immunochromatography assay (LFIA) is a simple technique that allows the rapid on-site detection of aflatoxins. The purpose of this review is to evaluate and compare the limits of detection reported in the most recent research articles, published between the years of 2015 and 2023. The limits of detection (LODs) were compared against the particle type and particle size, as well as other variables, to identify trends and correlations among the parameters. A growing interest in the use of different metal and non-metal nanoparticles was observed over the years of 2015–2023. The diameters of the nanoparticles used were reportedly between 1 nm and 100 nm. Most of these particles displayed lower LODs in the range of 0.01 to 1.0 ng/mL. Furthermore, there was a significant level of interest in detecting aflatoxin B1, perhaps due to its high level of toxicity and common appearance in food products. This study also compares the use of metallic and non-metallic nanoparticles in detecting aflatoxins and the dependence of nanoparticles' sizes on the detection range. Overall, the type of particle and particle size used in the development of LFIA strips can affect the sensitivity and LOD; hence, the optimization of these parameters and their modulation with respect to certain requirements can enhance the overall assay performance in terms of the reproducibility of results and commercialization. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have emerged as a promising tool for cancer treatment due to their unique physicochemical and biological properties. However, their clinical applications are limited by their potential cytotoxicity caused due to oxidation stress and non-specific cellular uptake pathways. To overcome these barriers, surface modifications of AgNPs have been proposed as an effective strategy to enhance their biocompatibility and specificity toward cancer cells. In this study, AgNPs were synthesised using the chemical reduction method and subsequently conjugated with various capping agents such as Polyvinylpyrrolidone (PVP) and Bovine Serum Albumin (BSA). Further, this study involves the synthesis of liposomes by using dipalmitoyl phosphatidylcholine lipid (DPPC) and cholesterol to increase the biocompatibility and bioavailability of AgNPs to MCF-7 breast cancer cells. In vitro, cytotoxicity studies were performed to determine which surface modification method exhibited the highest cytotoxic effect on the MCF-7 breast cancer cells, which was determined through the MTT assay. The AgNPs conjugated with BSA exhibited the highest cytotoxicity at the lowest dosage, with an IC50 of 2.5 μL/mL. The BSA-AgNPs induced a dose-dependent rise in cytotoxicity through the enhancement of nucleophilic dissolution of the AgNPs in cancer cells. In comparison, the unmodified AgNPs had an IC50 value of 3.0 μL/mL, while the PVP-modified AgNPs had an IC50 of 4.24 μL/mL. AgNPs encapsulated in liposomes had an IC50 value of 5.08 μL/mL, which shows that the encapsulation of AgNPs in liposomes controls their entry into cancer cells. The findings of this research have provided insights into the potential use of surface-modified AgNPs and liposomal encapsulated AgNPs as novel therapeutic tools to overcome the conventional treatment limitations of breast cancer cells. [ABSTRACT FROM AUTHOR]

Salmonella is a bacterial pathogen which is one of the leading causes of severe illnesses in humans. The current study involved the design and development of two methods, respectively using iron oxide nanoparticle (IONP) and iron core gold nanoparticle (ICGNP), conjugated with the Salmonella antibody and the fluorophore, 4-Methylumbelliferyl Caprylate (4-MUCAP), used as an indicator, for its selective and sensitive detection in contaminated food products. Twenty double-blind beverage samples, spiked with Salmonella enteritidis, Staphylococcus aureus, and Escherichia coli, were prepared in sterile Eppendorf® tubes at room temperature. The gold layer and spikes of ICGNPs increased the surface areas. The ratio of the surface area is 0.76 (IONPs/ICGNPs). The comparative sensitivity and specificity of the IONP-based and the ICGNP-based methods to detect Salmonella were determined. The ICGNP method shows the limit of detection is 32 Salmonella per mL. The ICGNPs had an 83.3% sensitivity and a 92.9% specificity value for the presence and detection of Salmonella. The IONP method resulted in a limit of detection of 150 Salmonella per mL, and a 66.7% sensitivity and 83.3% specificity for the presence and detection of Salmonella. The higher surface area of ICGNPs increases the efficiency of detection. The monitoring of Salmonella can thus be achieved by a rapid magnetic fluorescent assay using a smartphone for image capture and analyze, providing quantitative results. The findings from the present study would help to detect Salmonella rapidly in water. It can improve the microbial quality of water and food safety due to the presence of Salmonella in the water environment. [ABSTRACT FROM AUTHOR]

Glioma is considered the primary brain tumor to cause brain illnesses, and it is difficult to treat and shows resistance to various routine therapeutics. The most common treatments to cure glioma are the surgical removal of tumors followed by adjuvant chemotherapy and radiation therapy. The latest biocompatible interfaces have been incorporated into therapeutic modalities such as the targeted delivery of drugs using hydrogels to treat and manage brain glioma. This review illustrates the applications of the multimodal hydrogel as the carrier of therapeutics, gene therapy, therapeutic tactics, and glioma devices. The scientific articles were retrieved from 2019 to 2022 on Google Scholar and the Scopus database and screened to determine whether they were suitable for review. The 20 articles that fit the study are summarized in this review. These studies indicated that the sizes of the hydrogel range from 28 nm to 500 nm. There are 16 out of 20 articles that also explain the post-surgical application of hydrogels, and 13 out of 20 articles are employed in 3D culture and other structural manifestations of hydrogels. The pros of the hydrogel include the quick formulation for a sufficient filling of irregular damage sites, solubilizing hydrophobic drugs, continuously slowing drug release, provision of a 3D cell growth environment, improving efficacy, targetability of soluble biomolecules, increasing patient compliance, and decreased side effects. The cons of the hydrogel include difficult real-time monitoring, genetic manipulations, the cumbersome synchronized release of components, and lack of safety data. The prospects of the hydrogel may include the development of electronic hydrogel sensors that can be used to enhance guidance for the precise targeting patterns using patient-specific pathological idiosyncrasies. This technology has the potential to revolutionize the precision medicine approaches that would aid in the early detection and management of solid brain tumors. [ABSTRACT FROM AUTHOR]

The world is facing immense challenges in terms of food security, due to the combined impacts of the ever-increasing population and the adversity of climate change. In an attempt to counteract these factors, smart nutrient delivery systems, including nano-fertilizers, additives, and material coatings, have been introduced to increase food productivity to meet the growing food demand. Use of nanocarriers in agro-practices for sustainable farming contributes to achieving up to 75% nutrient delivery for a prolonged period to maintain nutrient availability in soil for plants in adverse soil conditions. In this context, sieve-like zeolites and the diversity in their structural morphologies have attracted increasing interest over recent years. Engineered nano-porous zeolites, also called aluminosilicates, are defined based on the presence of micro- (<2 nm), meso- (2–50 nm), and macropores (>50 nm), which can be employed as carriers of fertilizers due to their enhanced ion-exchange properties and adsorption capabilities. In this study, we provide a detailed overview of the production and optimization of hierarchical zeolite structures within the size range from micro- to nanometers, as well as the various top-down and bottom-up approaches which have been used to synthesize zeolites with a large surface area, tunable pore size, and high thermal stability, which make them an excellent candidate to be used in agronomy. The delivery of pesticides, insecticides, and fertilizers by loading them into nano-zeolites to manage the crop production without disrupting the soil health is discussed, as well as future perspectives of zeolites in the perpetual maintenance of soil productivity. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the most aggressive and commonly diagnosed brain cancer and is highly resistant to routine chemotherapeutic drugs. The present study involves the synthesis of Lignin-g-p (NIPAM-co-DMAEMA) gold nanogel, loaded with curcumin and piperine, to treat GBM. The ongoing study has the application potential to (1) overcome the limitations of drugs biodistribution, (2) enhance the toxicity of anticancer drugs against GBM, and (3) identify the drugs uptake pathway. Atom transfer radical polymerization was used to synthesize the Lignin-g-PNIPAM network, crosslinked with the gold nanoparticles (GNPs) to self-assemble into nanogels. The size distribution and morphological analysis confirmed that the drug-loaded gold nanogels are spherical and exist in the size of 180 nm. The single and combinatorial toxicity effects of curcumin- and piperine-loaded Lignin-g-p (NIPAM-co-DMAEMA) gold nanogels were studied against U-251 MG GBM cells. A cytotoxicity analysis displayed anticancer properties. IC50 of curcumin- and piperine-loaded gold nanogels were recorded at 30 μM and 35 μM, respectively. Immunostaining and Western blot analysis confirmed the protein expression of caspase-3 and cleaved caspase-3 in cells treated with drug-loaded nanogels. Kinetic drug release revealed 86% release of hybrid curcumin–piperine from gold nanogel after 250 min at pH 4. Atomic absorption spectroscopic analysis confirmed that the drug-loaded nanogels have better internalization or association with the cancer cells than the GNPs or nano-gels alone. Morphological studies further confirmed that the curcumin and piperine nanogels penetrate the cells via endocytic pathways and induce caspase-3-related apoptosis. The experimental evidence shows the enhanced properties of combinatorial curcumin–piperine gold nanogels (IC50: 21 μM) to overcome the limitations of conventional chemotherapeutic treatments of glioma cells. [ABSTRACT FROM AUTHOR]

The present study involved the bio-fabrication of silver nanoparticles (AgNPs) by using the Euphorbia helioscopia L. leaves aqueous extract to improve the production of secondary metabolites in industrially important sunflower (Helianthus annuus L.) plants. Phyto-fabrication of AgNPs was confirmed by using spectrophotometry, SEM imaging and X-ray diffraction analysis. The morphological and optical characterization manifested that the AgNPs are crystalline and exist in the size range of 30–100 nm. Various concentrations (10, 20, 40, 60, 80 and 100 mg/L) of AgNPs were applied in combinations on sunflower seeds and crop plants. The effects of biosynthesized AgNPs were evaluated for agro-morphological parameters (plant height, flowering initiation and seed weight), biochemical metabolites (chlorophyll, proline, soluble sugar, amino acid and protein contents) and enzymatic activities (superoxide dismutase and ascorbate peroxidase) in sunflower and 60 mg/L concentration of AgNPs on sunflower seeds and foliar sprays on plants in combination were found to be effective to elicit biochemical modifications to improve secondary metabolites. It was also observed experimentally that 60 mg/L concentration of AgNPs improved the biochemical, fatty acid and enzymatic attributes of sunflower plants, which in turn improved the plant agro-morphological parameters. Near-infrared spectroscopic analysis results confirmed the improvement in the seed quality, oil contents and fatty acid composition (palmitic acid, oleic acid and linoleic acid) after the applications of AgNPs. The findings of the present investigation confirm the exogenous applications of bio-fabricated AgNPs in combinations on seeds and plants to improve the plant yield, seed quality and secondary metabolite contents of the sunflower plants. [ABSTRACT FROM AUTHOR]