Green synthesis of silver nanoparticles using Teucrium polium leaf extract and assessment of their antitumor effects against MNK45 human gastric cancer cell line

A narrative review on the use of Green synthesized metallic nanoparticles for targeted cancer therapy

Cancer is a leading cause of death worldwide. While traditional and synthetic medical therapies are in place for cancer treatment, their effectiveness is hindered by various limitations, such as toxic side effects, limited availability, and high costs. In recent years, a promising alternative approach has emerged in the form of green-synthesized metallic nanoparticles (MNPs), which offer targeted cancer therapy. These nanoparticles (NPs) have garnered significant attention from cancer researchers owing to their natural or surface-induced anticancer properties, versatility of metals as agents, and eco-friendly nature. This approach may positively impact healthy cells surrounding the cancerous cells. Green-synthesized MNPs have gained popularity in cancer management because of their ease of handling in the laboratory and the affordability of starting materials compared to synthetic methods. This review analyzes green-synthesized MNPs for targeted cancer therapy, highlighting tumor-targeting strategies, synthesis methods, and clinical challenges. Unlike general reviews, it compares plant-, microbial-, and enzyme-mediated synthesis approaches, emphasizing their impact on nanoparticle stability, functionalization, and interactions with the tumor microenvironment for enhanced therapeutic efficacy.

Exploring the green synthesis of silver nanoparticles using natural extracts and their potential for cancer treatment

Silver nanoparticles (AgNPs) have attracted increasing attention in nanomedicine, with versatile applications in drug delivery, antimicrobial treatments, and cancer therapies. While chemical synthesis remains a common approach for AgNP production, ensuring environmental sustainability requires a shift toward eco-friendly, "green" synthesis techniques. This article underscores the promising role of plant extracts in the green synthesis of AgNPs, highlighting the importance of their natural sources and diverse bioactive compounds. Various characterization methods for these nanomaterials are also reviewed. Furthermore, the anticancer potential of green AgNPs (Gr-AgNPs) is examined, focusing on their mechanisms of action and the challenges to their clinical implementation. Finally, future directions in the field are discussed.

Nitrate levels in vegetables from markets in Tehran, Iran

This study is aimed at measuring nitrate levels in different vegetables from Tehran's markets that are consumed raw and fresh and to evaluate human health risk. Basil, parsley, radish leaves, cress, leek, radish, spring onion were randomly collected from local markets and the nitrate content was analysed by spectrophotometry. Average nitrate levels in the samples were 40.1, 45.2, 50.0, 51.8, 55.4, 90.2 and 110 mg kg-1 in parsley, leek, basil, radish leaves, cress, radish and spring onion, respectively. The average content in all samples was below Iranian standard limits. Tuber vegetables had significantly higher nitrate content than (green) leafy vegetables.

The Effect of ZnO Nanoparticles Functionalized with Glutamine and Conjugated with Thiosemicarbazide on Triggering of Apoptosis in the Adenocarcinoma Gastric Cell Line

Background

Gastric carcinoma is the fourth most common malignancy worldwide. Conjugation of metal nanoparticles with thiosemicarbazones has shown considerable anti-cancer potential.

Materials and Methods

Zinc oxide nanoparticles (ZnO NPs) were synthesized, functionalized by glutamine, and conjugated with thiosemicarbazide (ZnO@Gln-TSC). Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy imaging, energy-dispersive X-ray, DLS, and zeta potential were used to characterize the NPs. The toxicity of ZnO NPs, TSC, ZnO@Gln-TSC NPs, and oxaliplatin in AGS cells and ZnO NPs and ZnO@Gln-TSC NPs in HEK293 cells was investigated by MTT assay. Cell apoptosis was evaluated by flow cytometry, caspase-3 activity, and Hoechst staining assays. The intra-cellular reactive oxygen species level and expression level of the CASP3 gene in AGS cells treated with ZnO@Gln-TSC NPs were evaluated.

Results

The NPs were in the size range of 20 to 70 nm. The DLS and zeta potential were 374 nm and -31.7 mV, respectively. In MTT, the IC50 of ZnO, TSC, oxaliplatin, and ZnO@Gln-TSC NPs for AGS cells were 130, 80.5, 67.7, and 9.8 μg/mL, respectively, and the IC50 of ZnO and ZnO@Gln-TSC NPs for HEK293 cells were 215 and 150.5 μg/mL, respectively. Flow cytometry showed higher apoptosis in the cell treated with the NPs and TSC. Apoptotic features, including cell shrinkage, were recognized. A significant increase of 5.9 folds in the level of ROS was noticed. The activity of caspase-3 and the expression level of the CASP3 gene were increased by1.83 and 1.6 folds after exposure to ZnO@Gln-TSC NPs, respectively.

Conclusions

This study revealed the anti-cancer potential of ZnO@Gln-TSC NPs to be used for gastric cancer treatment after further in vitro and in vivo assays.

Biogenic silver nanomaterials synthesized from Ocimum sanctum leaf extract exhibiting robust antimicrobial and anticancer activities: Exploring the therapeutic potential

There is a surge in antibiotic consumption because of the emergence of resistance among microbial pathogens. In the escalating challenge of antibiotic resistance in microbial pathogens, silver nanoparticles (AgNPs)-mediated therapy has proven to be the most effective and alternative therapeutic strategy for bacterial infections and cancer treatment. This study aims to explore the potential of OsAgNPs derived from Ocimum sanctum's aqueous leaf extract as antimicrobial agents and anticancer drug delivery modalities. This study utilized a plant extract derived from Ocimum sanctum (Tulsi) leaves to synthesize silver nanoparticles (OsAgNPs), that were characterized by FTIR, TEM, SEM, and EDX. OsAgNPs were assessed for their antibacterial and anticancer potential. TEM analysis unveiled predominantly spherical or oval-shaped OsAgNPs, ranging in size from 4 to 98 nm. The (MICs) of OsAgNPs demonstrated a range from 0.350 to 19.53 μg/ml against clinical, multidrug-resistant (MDR), and standard bacterial isolates. Dual labelling with ethidium bromide and acridine orange demonstrated that OsAgNPs induced apoptosis in HeLa cells. The OsAgNPs-treated cells showed yellow-green fluorescence in early-stage apoptotic cells and orange fluorescence in late-stage cells. Furthermore, OsAgNPs exhibited a concentration-dependent decrease in HeLa cancer cell viability, with an IC50 value of 90 μg/ml noted. The study highlights the remarkable antibacterial efficacy of OsAgNPs against clinically significant bacterial isolates, including antibiotic-resistant strains. These results position the OsAgNPs as prospective therapeutic agents with the potential to address the growing challenges posed by antibiotic resistance and cervical cancer.

Sublingual Administration of Teucrium Polium-Loaded Nanofibers with Ultra-Fast Release in the Treatment of Diabetes Mellitus: In Vitro and In Vivo Evaluation

In this study, Teucrium polium (TP) methanolic extract, which has antidiabetic activity and protects the β-cells of the pancreas, was loaded in polyethylene oxide/sodium alginate nanofibers by electrospinning and administered sublingually to evaluate their effectiveness in type-2 diabetes mellitus (T2DM) by cell culture and in vivo studies. The gene expressions of insulin, glucokinase, GLUT-1, and GLUT-2 improved in TP-loaded nanofibers (TPF) on human beta cells 1.1B4 and rat beta cells BRIN-BD11. Fast-dissolving (<120 s) sublingual TPF exhibited better sustainable anti-diabetic activity than the suspension form, even in the twenty times lower dosage in streptozotocin/nicotinamide-induced T2DM rats. The levels of GLP-1, GLUT-2, SGLT-2, PPAR-γ, insulin, and tumor necrosis factor-alpha were improved. TP and TPF treatments ameliorated morphological changes in the liver, pancreas, and kidney. The fiber diameter increased, tensile strength decreased, and the working temperature range enlarged by loading TP in fibers. Thus, TPF has proven to be a novel supportive treatment approach for T2DM with the features of being non-toxic, easy to use, and effective.

Applications of Green Synthesized Metal Nanoparticles - a Review

Green nanotechnology is an emerging field of science that focuses on the production of nanoparticles by living cells through biological pathways. This topic plays an extremely imperative responsibility in various fields, including pharmaceuticals, nuclear energy, fuel and energy, electronics, and bioengineering. Biological processes by green synthesis tools are more suitable to develop nanoparticles ranging from 1 to 100 nm compared to other related methods, owing to their safety, eco-friendliness, non-toxicity, and cost-effectiveness. In particular, the metal nanoparticles are synthesized by top-down and bottom-up approaches through various techniques like physical, chemical, and biological methods. Their characterization is very vital and the confirmation of nanoparticle traits is done by various instrumentation analyses such as UV-Vis spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM), annular dark-field imaging (HAADF), and intracranial pressure (ICP). In this review, we provide especially information on green synthesized metal nanoparticles, which are helpful to improve biomedical and environmental applications. In particular, the methods and conditions of plant-based synthesis, characterization techniques, and applications of green silver, gold, iron, selenium, and copper nanoparticles are overviewed.

Novel biosynthesis of gold nanoparticles for multifunctional applications: Electrochemical detection of hydrazine and treatment of gastric cancer

In this work, an environmentally friendly strategy was used to synthesize gold nanoparticles (Au NPs) using Olea europaea (olive) fruit. Transmission electron microscopy (TEM), UV-Vis spectroscopy, X-ray diffraction (XRD) and energy-dispersive X-ray (EDX) were used to characterize the physicochemical properties of the synthesized NPs. An Au NPs modified glassy carbon electrode was used to investigate the direct electrochemical oxidation of hydrazine. The suggested hydrazine sensor has good performance, such as a wide linear range (2.5-275 μM), low limit of detection (0.09 μM), notable selectivity and excellent reproducibility (RSD = 2.2%). The in-vitro cytotoxicity of three human cancer cell lines (KATOIII, NCI-N87, and SNU-16) was also explored with various concentrations of Au NPs prepared from olive fruit extract. Bio-synthesized Au NPs were found to have cytotoxic properties against gastric cancer in humans based on MTT assay protocol. The obtained results show that green synthesized Au NPs can be successfully employed in electrochemical sensing and cancer treatment applications.

Bioinspired Multifunctional Silver Nanoparticles for Optical Sensing Applications: A Sustainable Approach

Silver nanoparticles developed via biosynthesis are the most fascinating nanosized particles and encompassed with excellent physicochemical properties. The bioinspired nanoparticles with different shapes and sizes have attracted huge attention due to their stability, low cost, environmental friendliness, and use of less hazardous chemicals. This is an ideal method for synthesizing a range of nanosized metal particles from plants and biomolecules. Optical biosensors are progressively being fabricated for the attainment of sustainability by using opportunities offered by nanotechnology. This review focuses mainly on tuning the optical properties of the metal nanoparticles for optical sensing to explore the importance and applications of bioinspired silver nanoparticles. Further, this review deliberates the role of bioinspired silver nanoparticles (Ag NPs) in biomedical, agricultural, environmental, and energy applications. Profound insight into the antimicrobial properties of these nanoparticles is also appreciated. Tailor-made bioinspired nanoparticles with effectuating characteristics can unsurprisingly target tumor cells and distribute enwrapped payloads intensively. Existing challenges and prospects of bioinspired Ag NPs are also summarized. This review is expected to deliver perceptions about the progress of the next generation of bioinspired Ag NPs and their outstanding performances in various fields by promoting sustainable practices for fabricating optical sensing devices.

Exploring the Biomedical Applications of Biosynthesized Silver Nanoparticles Using Perilla frutescens Flavonoid Extract: Antibacterial, Antioxidant, and Cell Toxicity Properties against Colon Cancer Cells

The present study reports the biomimetic synthesis of silver nanoparticles (AgNPs) using a simple, cost effective and eco-friendly method. In this method, the flavonoid extract of Perilla frutescens (PFFE) was used as a bioreduction agent for the reduction of metallic silver into nanosilver, called P. frutescens flavonoid extract silver nanoparticles (PFFE-AgNPs). The Ultraviolet-Visible (UV-Vis) spectrum showed a characteristic absorption peak at 440 nm that confirmed the synthesis of PFFE-AgNPs. A Fourier transform infrared spectroscopic (FTIR) analysis of the PFFE-AgNPs revealed that flavonoids are involved in the bioreduction and capping processes. X-ray diffraction (XRD) and selected area electron diffraction (SAED) patterns confirmed the face-centered cubic (FCC) crystal structure of PFFE-AgNPs. A transmission electron microscopic (TEM) analysis indicated that the synthesized PFFE-AgNPs are 20 to 70 nm in size with spherical morphology and without any aggregation. Dynamic light scattering (DLS) studies showed that the average hydrodynamic size was 44 nm. A polydispersity index (PDI) of 0.321 denotes the monodispersed nature of PFFE-AgNPs. Further, a highly negative surface charge or zeta potential value (-30 mV) indicates the repulsion, non-aggregation, and stability of PFFE-AgNPs. PFFE-AgNPs showed cytotoxic effects against cancer cell lines, including human colon carcinoma (COLO205) and mouse melanoma (B16F10), with IC50 concentrations of 59.57 and 69.33 μg/mL, respectively. PFFE-AgNPs showed a significant inhibition of both Gram-positive (Listeria monocytogens and Enterococcus faecalis) and Gram-negative (Salmonella typhi and Acinetobacter baumannii) bacteria pathogens. PFFE-AgNPs exhibited in vitro antioxidant activity by quenching 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2) free radicals with IC50 values of 72.81 and 92.48 µg/mL, respectively. In this study, we also explained the plausible mechanisms of the biosynthesis, anticancer, and antibacterial effects of PFFE-AgNPs. Overall, these findings suggest that PFFE-AgNPs have potential as a multi-functional nanomaterial for biomedical applications, particularly in cancer therapy and infection control. However, it is important to note that further research is needed to determine the safety and efficacy of these nanoparticles in vivo, as well as to explore their potential in other areas of medicine.

Antibacterial potential of biosynthesized silver nanoparticles using Nepeta sessilifolia Bunge and Salvia hydrangea DC. ex Benth. extracts from the natural habitats of Iran's Rangelands

BACKGROUND

Nowadays, the use of herbal extracts for the production of nanoparticles has attracted a lot of attention due to the fast reaction, economy, and compatibility with the environment. The aim of the present study is the biosynthesis of silver nanoparticles from the extracts of Nepeta sessilifolia Bunge and Salvia hydrangea DC. ex Benth. and their antibacterial activity was measured.

METHODS

For this purpose, the flowering branch of N. sessilifolia and the flower of S. hydrangea were randomly collected from three places, respectively, from the rangelands of Aqdash Mountain and Biabe in Isfahan province, Iran in May 2021. After extracting aqueous extracts by hot method, silver nanoparticles were synthesized by the biological method. Green synthesized silver nanoparticles were analyzed by UV-Vis spectroscopy, XRD, FTIR, and FESEM-EDAX. The antibacterial effect was evaluated by diffusion method in agar and determination of minimum growth inhibitory and lethal concentration (MIC and MBC) by dilution method in liquid culture medium.

RESULTS

Based on the results of UV-Vis spectroscopy, silver nanoparticles synthesized from N. sessilifolia and S. hydrangea had distinct absorption peaks at wavelengths of 407 to 424 nm and 414 to 415 nm, respectively. The crystalline nature of these synthetic silver nanoparticles was confirmed by XRD. FESEM analysis showed that the size of biosynthesized silver nanoparticles from N. sessilifolia and S. hydrangea extracts were 10-50 nm and 10-80 nm, respectively, and were cubic. The results of diffusion in agar showed that the largest diameter of the growth inhibition zone belonging to the synthetic silver nanoparticles from both extracts of N. sessilifolia (~ 26.00 mm) and S. hydrangea (~ 23.50 mm) was against Gram-positive bacteria Staphylococcus aureus. The most vigorous killing activity by synthetic silver nanoparticles from N. sessilifolia extract was against Klebsiella pneumoniae with a value of 250 μg/mL, two times stronger than rifampin.

CONCLUSION

Therefore, the studied extracts can be suitable options for fast and safe green synthesis of silver nanoparticles effective against some bacterial strains. These synthetic silver nanoparticles can be used as possible options and have strong potential for the production of natural antibiotics.

Mapping the Progress in Surface Plasmon Resonance Analysis of Phytogenic Silver Nanoparticles with Colorimetric Sensing Applications

Nanotechnology is gaining enormous attention as the most dynamic research area in science and technology. It involves the synthesis and applications of nanomaterials in diverse fields including medical, agriculture, textiles, food technology, cosmetics, aerospace, electronics, etc. Silver nanoparticles (AgNPs) have been extensively used in such applications due to their excellent physicochemical, antibacterial, and biological properties. The use of plant extract as a biological reactor is one of the most promising solutions for the synthesis of AgNPs because this process overcomes the drawbacks of physical and chemical methods. This review article summarizes the plant-mediated synthesis process, the probable reaction mechanism, and the colorimetric sensing applications of AgNPs. Plant-mediated synthesis parameters largely affect the surface plasmon resonance (SPR) characteristic due to the changes in the size and shape of AgNPs. These changes in the size and shape of plant-mediated AgNPs are elaborately discussed here by analyzing the surface plasmon resonance characteristics. Furthermore, this article also highlights the promising applications of plant-mediated AgNPs in sensing applications regarding the detection of mercury, hydrogen peroxide, lead, and glucose. Finally, it describes the future perspective of plant-mediated AgNPs for the development of green chemistry.

Anti-cancer activity of green synthesized silver nanoparticles using Ardisia gigantifolia leaf extract against gastric cancer cells

Using extracts from herbs for silver nanoparticle synthesis is attracting attention for its anticancer activity. Ardisia gigantifolia is a herb used in traditional Chinese medicine for treating stomach ailments, and some compounds isolated from this plant exhibit the inhibitory activity against different cancer cells. However, the synthesis of silver nanoparticle using extract of Ardisia gigantiflia leaves and their anti-cancer activity was not reported. In this report, the green synthesized silver nanoparticles using Ardisia gigantiflia extract (Arg-AgNPs) has average diameter of 6 nm with functional groups including O-H, C-H, and CO founded on the surface of these nanoparticles. The viability assays results revealed Arg-AgNPs reduced gastric cancer cell proliferation in a dose-dependent manner, with IC₅₀ values of 1.37 and 0.65 μg/mL for AGS cells and 1.03 and 0.96 μg/mL for MKN45 cells. Arg-AgNPs caused cell cycle arrest at the G0/G1 phase and suppressed cell migration. Additionally, Arg-AgNPs significantly increased the percentage of senescent cells and promoted overproduction of reactive oxygen species (ROS) compared to the control. Thus, this study indicates that Arg-AgNPs can be considered as a promising candidate against human gastric cancer cells.

Novel zinc oxide nanoparticles of Teucrium polium suppress the malignant progression of gastric cancer cells through modulating apoptotic signaling pathways and epithelial to mesenchymal transition

Management of gastric cancer is still challenging due to resistance to current chemotherapeutics and recurrent disease. Moreover, green- synthesized zinc oxide nanoparticles (ZnO-NPs) using natural resources are one of the most promising therapeutic agents for anticancer therapy. Here we report the facile green synthesis and characterization of ZnO-NPs from Teucrium polium (TP-ZnO-NP) herb extract and the anticancer activities of these nanoparticles on gastric cancer cells. Facile green synthesis of TP-ZnO-NP was achieved using zinc acetate dihydrate. For the characterization of TP-ZnO-NP, UV-vis spectroscopy, FTIR, SEM, XRD and EDX analyses were performed. Antiproliferative and anticancer activities of TP-ZnO-NP were explored using the HGC-27 gastric cancer cell line model. MTT cell viability and colony formation assays were used for the analysis of cell proliferation and migration. Wound healing assay was used to analyze the migration capacities of cells. Annexin V/PI double staining, DNA ladder assay, and Acridine orange/Ethidium bromide staining were performed to analyze the induction of apoptosis. qPCR was used to determine gene expression levels of apoptotic and epithelial to mesenchymal transition marker genes. The aqueous extract of TP served as both a reducing and capping agent for the successful biosynthesis of zinc oxide nanoparticles. Remarkably, synthesized TP-ZnO-NPs were found to have significant antiproliferative and anticancer activities on HGC-27 gastric cancer cells. Collectively, current data suggest that TP-ZnO-NP is a novel and promising anticancer agent for future therapeutic interventions in gastric cancer.

Recent advances in targeted antibacterial therapy basing on nanomaterials

Bacterial infection has become one of the leading causes of death worldwide, particularly in low-income countries. Despite the fact that antibiotics have provided successful management in bacterial infections, the long-term overconsumption and abuse of antibiotics has contributed to the emergence of multidrug resistant bacteria. To address this challenge, nanomaterials with intrinsic antibacterial properties or that serve as drug carriers have been substantially developed as an alternative to fight against bacterial infection. Systematically and deeply understanding the antibacterial mechanisms of nanomaterials is extremely important for designing new therapeutics. Recently, nanomaterials-mediated targeted bacteria depletion in either a passive or active manner is one of the most promising approaches for antibacterial treatment by increasing local concentration around bacterial cells to enhance inhibitory activity and reduce side effects. Passive targeting approach is widely explored by searching nanomaterial-based alternatives to antibiotics, while active targeting strategy relies on biomimetic or biomolecular surface feature that can selectively recognize targeted bacteria. In this review article, we summarize the recent developments in the field of targeted antibacterial therapy based on nanomaterials, which will promote more innovative thinking focusing on the treatment of multidrug-resistant bacteria.

Activities against Lung Cancer of Biosynthesized Silver Nanoparticles: A Review

Nanomedicine is an interdisciplinary field where nanostructured objects are applied to treat or diagnose disease. Nanoparticles (NPs) are a special class of materials at nanometric scale that can be prepared from lipids, polymers, or noble metals through bottom-up approaches. Biological synthesis is a reliable, sustainable, and non-toxic bottom-up method that uses phytochemicals, microorganisms, and enzymes to induce the reduction of metal ions into NPs. Silver (Ag) NPs exhibit potent therapeutic properties that can be exploited to overcome the limitations of current treatment modalities for human health issues such as lung cancer (LC). Here, we review the preparation of AgNPs using biological synthesis and their application against LC using in vitro and in vivo models. An overview of the staging, diagnosis, genetic mutations, and treatment of LC, as well as its main subtypes, is presented. A summary of the reaction mechanisms of AgNPs using microbial cell cultures, plant extracts, phytochemicals, and amino acids is included. The use of capping agents in the biosynthesis of AgNPs with anticancer activity is also detailed. The history and biological activities of metal-based nanostructures synthesized with gold, copper, palladium, and platinum are considered. The possible anticancer mechanisms of AgNPs against LC models are covered. Our perspective about the future of AgNPs in LC treatment and nanomedicine is added.

Progress in Laser Ablation and Biological Synthesis Processes: "Top-Down" and "Bottom-Up" Approaches for the Green Synthesis of Au/Ag Nanoparticles

Because of their small size and large specific surface area, nanoparticles (NPs) have special properties that are different from bulk materials. In particular, Au/Ag NPs have been intensively studied for a long time, especially for biomedical applications. Thereafter, they played a significant role in the fields of biology, medical testing, optical imaging, energy and catalysis, MRI contrast agents, tumor diagnosis and treatment, environmental protection, and so on. When synthesizing Au/Ag NPs, the laser ablation and biosynthesis methods are very promising green processes. Therefore, this review focuses on the progress in the laser ablation and biological synthesis processes for Au/Ag NP generation, especially in their fabrication fundamentals and potential applications. First, the fundamentals of the laser ablation method are critically reviewed, including the laser ablation mechanism for Au/Ag NPs and the controlling of their size and shape during fabrication using laser ablation. Second, the fundamentals of the biological method are comprehensively discussed, involving the synthesis principle and the process of controlling the size and shape and preparing Au/Ag NPs using biological methods. Third, the applications in biology, tumor diagnosis and treatment, and other fields are reviewed to demonstrate the potential value of Au/Ag NPs. Finally, a discussion surrounding three aspects (similarity, individuality, and complementarity) of the two green synthesis processes is presented, and the necessary outlook, including the current limitations and challenges, is suggested, which provides a reference for the low-cost and sustainable production of Au/Ag NPs in the future.

Inhibition of Phytopathogenic and Beneficial Fungi Applying Silver Nanoparticles In Vitro

In the current research, our work measured the effect of silver nanoparticles (AgNP) synthesized from Larrea tridentata (Sessé and Moc. ex DC.) on the mycelial growth and morphological changes in mycelia from different phytopathogenic and beneficial fungi. The assessment was conducted in Petri dishes, with Potato-Dextrose-Agar (PDA) as the culture medium; the AgNP concentrations used were 0, 60, 90, and 120 ppm. Alternaria solani and Botrytis cinerea showed the maximum growth inhibition at 60 ppm (70.76% and 51.75%). Likewise, Macrophomina spp. required 120 ppm of AgNP to achieve 65.43%, while Fusarium oxisporum was less susceptible, reaching an inhibition of 39.04% at the same concentration. The effect of silver nanoparticles was inconspicuous in Pestalotia spp., Colletotrichum gloesporoides, Phytophthora cinnamomi, Beauveria bassiana, Metarhizium anisopliae, and Trichoderma viridae fungi. The changes observed in the morphology of the fungi treated with nanoparticles were loss of definition, turgidity, and constriction sites that cause aggregations of mycelium, dispersion of spores, and reduced mycelium growth. AgNP could be a sustainable alternative to managing diseases caused by Alternaria solani and Macrophomina spp.

Green Synthesis of Silver Nanoparticles from Aqueous Extract of Tinospora crispa Stems Accelerate Wound Healing in Rats

GRAPHICAL ABSTRACT

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Optimization, Characterization, and Anticancer Potential of Silver Nanoparticles Biosynthesized Using Olea europaea

Green synthesis has attracted significant attention as an eco-friendly, low-cost, energy-efficient, and non-toxic method for preparing silver nanoparticles (AgNPs) for cancer therapy. This study optimized the green synthesis of AgNPs using Olea europaea extracts and evaluated their anticancer potential. The biosynthesized AgNPs were characterized using various methods, showing stable AgNPs with a desirable morphology and high yield, improving the properties of AgNPs for various medicinal applications. The biosynthesized AgNPs were predominantly spherical, with small sizes ranging from 13 to 21 nm and highly stable at −23 and −24 mV. The findings of this study suggest that green-synthesized AgNPs using Olea europaea and sunlight possess significant anticancer activity against cancer cells in vitro. Further investigation of green synthesis would help to form high-quality AgNPs that have promising potential in treating disease and fighting undesirable pathogens.

Green Biosynthesis of Silver Nanoparticles from Moringa oleifera Leaves and Its Antimicrobial and Cytotoxicity Activities

The plant occupied the largest area in the biosynthesis of silver nanoparticles, especially the medicinal plants, and it has shown great potential in biotechnology applications. In this study, green synthesis of silver nanoparticles from Moringa oleifera leaves extract and its antifungal and antitumor activities were investigated. The formation of silver nanoparticles was observed after 1 hour of preparation color changing. The ultraviolet and visible spectrum, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize synthesis particles. Ultraviolet and visible spectroscopy showed a silver surface plasmon resonance band at 434 nm. Fourier transform infrared analysis shows the possible interactions between silver and bioactive molecules in Moringa oleifera leaves extracts, which may be responsible for the synthesis and stabilization of silver nanoparticles. X-ray diffraction showed that the particles were a semicubic crystal structure and with a size of 38.495 nm. Scanning electron microscopy imaging shows that the atoms are spherical in shape and the average size is 17 nm. The transmission electron microscopy image demonstrated that AgNPs were spherical and semispherical particles with an average of (50–60) nm. The nanoparticles also showed potent antimicrobial activity against pathogenic bacteria and fungi using the well diffusion method. Candida glabrata found that the concentration of 1000 μg/mL exhibited the highest inhibition. As for bacteria, the concentration of 1000 μg/mL appeared to be the inhibition against Staphylococcus aureus. Moringa oleifera AgNPs inhibited human melanoma cells A375 line significant concentration-dependent cytotoxic effects. The powerful bioactivity of the green synthesized silver nanoparticles from medical plants recommends their biomedical use as antimicrobial as well as cytotoxic agents.

Optimized Green Synthesis and Anticancer Potential of Silver Nanoparticles Using Juniperus procera Extract Against Lung Cancer Cells

Silver nanoparticles (AgNPs) have been considered promising candidates for medical practices in various fields. This study proposed an efficient, economical, uncomplicated, and reliable method to synthesize AgNPs utilizing leaf and fruit extracts of Juniperus procera (J. procera) as capping, reducing, and stabilizing agents. The study includes optimizing the green synthesis conditions to produce stable AgNPs with high yields, acceptable particle size, and shape, hence, AgNPs may be used for different medical purposes through the improvement of their properties. Several spectroscopic and other analyses performed characterization of the fabricated AgNPs, and the results show stable and spherical AgNPs between 14 and 18 nm in size. The study also evaluated the anticancer activities of the biosynthesized AgNPs using J. procera fruit and leaf extracts against in vitro lung cancer A549 and H1975 cells. The results demonstrate the high toxicity of the biosynthesized AgNPs against in vitro lung cancer cells, supporting therapeutic and biomedical applications of AgNPs.

Applications of Gold and Silver Nanoparticles in Theranostics

Nanotechnology sculptures the current scenario of science and technology. The word nano refers 'small' which ranges from 10 to 100 nm in size. Silver and gold nanoparticles can be synthesized at nanoscale and have unique biological properties like antibacterial, antifungal, antiviral, antiparasitic, antiplatelet, anti-inflammatory, and anti-tumor activity. In this mini review, we shall discuss the various applications of silver and gold nanoparticles (AuNPs) in the field of therapy, imaging, biomedical devices and in cancer diagnosis. The usage of silver nanoparticles(AgNPs) in dentistry and dental implants, therapeutic abilities like wound dressings, silver impregnated catheters, ventricular drainage catheters, combating orthopedic infections, and osteointegration will be elaborated. Gold nanoparticles in recent years have garnered large importance in bio medical applications. They are being used in diagnosis and have recently seen a surge in therapeutics. In this mini review, we shall see about the various applications of AuNP and AgNP, and highlight their evolution in theranostics.

Optimization of Synthesis of Silver Nanoparticles Conjugated with Lepechinia meyenii (Salvia) Using Plackett-Burman Design and Response Surface Methodology—Preliminary Antibacterial Activity

In the present investigation, an ethanolic fraction (EF) of Lepechinia meyenii (salvia) was prepared and fractionated by gradient column chromatography, and the main secondary metabolites present in the EF were identified by HPLC-MS. Silver nanoparticles (AgNPs) were synthesized and conjugated with the EF of Lepechinia meyenii (salvia). The AgNPs synthesis was optimized using Plackett-Burman design and response surface methodology (RSM), considering the following independent variables: stirring speed, synthesis pH, synthesis time, synthesis temperature and EF volume. The AgNPs synthesized under the optimized conditions were characterized by UV visible spectroscopy (UV-VIS), Fourier Transform Infrared Spectroscopy (FT-IR), Dynamic Light Scattering (DLS) and Scanning Transmission Electron Microscopy (STEM). The antibacterial activity of the AgNPs against Staphylococcus aureus (ATCC® 25923) was evaluated. The following flavonoids were identified: rosmarinic acid, diosmin and hesperetin-7-O-rutinoside. The optimized conditions for the synthesis of nanoparticles were pH 9.45, temperature 49.8 °C, volume of ethanolic fraction 152.6 µL and a reaction time of 213.2 min. The obtained AgNPs exhibited an average size of 43.71 nm and a resonance plasmon of 410–420 nm. Using FT-IR spectroscopy, the disappearance of the peaks between 626.50 and 1379.54 cm−1 was evident with the AgNPs, which would indicate the participation of these functional groups in the synthesis and protection of the nanoparticles. A hydrodynamic size of 47.6 nm was obtained by DLS, while a size of 40–60 nm was determined by STEM. The synthesized AgNPs conjugated with the EF showed a higher antibacterial activity than the EF alone. These results demonstrate that the AgNPs synthesized under optimized conditions conjugated with the EF of the Lepechinia meyenii (salvia) presented an increased antibacterial activity.

Biosynthesis of silver nanoparticles using three different fruit extracts: Characterization, formation mechanism and estrogen removal

Plant-mediated synthesis of silver nanoparticles (Ag NPs) is a green and economically viable method, which can offer numerous benefits over traditional chemical and physical methods. In this paper, three fruit extracts (tomato, orange, and grapefruit) served simultaneously as stabilizing and reducing agents during the biosynthesis of Ag NPs. The formation of Ag NPs, were monitored using the UV-visible absorption spectra of Ag NPs which exhibited three distinct bands centered at 439, 413, and 410 nm. SEM and TEM analysis indicated that these bands corresponded to three distinct spherical-shaped Ag NPs having average particle sizes of 73, 24, and 31 nm, respectively. XRD and EDS spectral analyses were used to verify the degree of crystallinity, nanostructure, and presence of Ag NPs. Advanced analysis using XPS, FTIR, and GC-MS indicated that the Ag NPs were coated with a variety of organic compounds including acids, aldehydes, esters, and ketones, indicating that fruit derived phytochemicals had a significant role in synthesis, and subsequently a mechanism of Ag NPs formation was proposed. The fabricated nanoparticles were also successfully used in Fenton-like oxidation for the environmental remediation of estrone and estriol, with removal efficiencies of 52.1 and 35.9%, respectively.

Novel Drug Delivery Systems as an Emerging Platform for Stomach Cancer Therapy

Cancer has long been regarded as one of the world's most fatal diseases, claiming the lives of countless individuals each year. Stomach cancer is a prevalent cancer that has recently reached a high number of fatalities. It continues to be one of the most fatal cancer forms, requiring immediate attention due to its low overall survival rate. Early detection and appropriate therapy are, perhaps, of the most difficult challenges in the fight against stomach cancer. We focused on positive tactics for stomach cancer therapy in this paper, and we went over the most current advancements and progressions of nanotechnology-based systems in modern drug delivery and therapies in great detail. Recent therapeutic tactics used in nanotechnology-based delivery of drugs aim to improve cellular absorption, pharmacokinetics, and anticancer drug efficacy, allowing for more precise targeting of specific agents for effective stomach cancer treatment. The current review also provides information on ongoing research aimed at improving the curative effectiveness of existing anti-stomach cancer medicines. All these crucial matters discussed under one overarching title will be extremely useful to readers who are working on developing multi-functional nano-constructs for improved diagnosis and treatment of stomach cancer.

Green Synthesis of a Novel Silver Nanoparticle Conjugated with Thelypteris glandulosolanosa (Raqui-Raqui): Preliminary Characterization and Anticancer Activity

In the last decade, the green synthesis of nanoparticles has had a prominent role in scientific research for industrial and biomedical applications. In this current study, silver nitrate (AgNO3) was reduced and stabilized with an aqueous extract of Thelypteris glandulosolanosa (Raqui-raqui), forming silver nanoparticles (AgNPs-RR). UV-vis spectrophotometry, dynamic light scattering (DLS), and scanning transmission electron microscopy (STEM) were utilized to analyze the structures of AgNPs-RR. The results from this analysis showed a characteristic peak at 420 nm and a mean hydrodynamic size equal to 39.16 nm, while the STEM revealed a size distribution of 6.64–51.00 nm with an average diameter of 31.45 nm. Cellular cytotoxicity assays using MCF-7 (ATCC® HTB-22™, mammary gland breast), A549 (ATCC® CCL-185, lung epithelial carcinoma), and L929 (ATCC® CCL-1, subcutaneous connective tissue of Mus musculus) demonstrated over 42.70% of MCF-7, 59.24% of A549, and 8.80% of L929 cells had cell death after 48 h showing that this nanoparticle is more selective to disrupt neoplastic than non-cancerous cells and may be further developed into an effective strategy for breast and lung cancer treatment. These results demonstrate that the nanoparticle surfaces developed are complex, have lower contact angles, and have excellent scratch and wear resistance.

Biomedical applications of metallic nanoparticles in cancer: Current status and future perspectives

The current advancements in nanotechnology are as an outcome of the development of engineered nanoparticles. Various metallic nanoparticles have been extensively explored for various biomedical applications. They attract lot of attention in biomedical field due to their significant inert nature, and nanoscale structures, with size similar to many biological molecules. Their intrinsic characteristics which include electronic, optical, physicochemical and, surface plasmon resonance, that can be changed by altering certain particle characteristics such as size, shape, environment, aspect ratio, ease of synthesis and functionalization properties have led to numerous applications in various fields of biomedicine. These include targeted drug delivery, sensing, photothermal and photodynamic therapy, imaging, as well as the modulation of two or three applications. The current article also discusses about the various properties of metallic nanoparticles and their applications in cancer imaging and therapeutics. The associated bottlenecks related to their clinical translation are also discussed.

Very rapid synthesis of highly efficient and biocompatible Ag2Se QD phytocatalysts using ultrasonic irradiation for aqueous/sustainable reduction of toxic nitroarenes to anilines with excellent yield/selectivity at room temperature

There are many problems associated with the synthesis of nanocatalysts and catalytic reduction of nitroarenes - e.g., high temperatures, costs, long reaction/synthesis process times, the toxicity of chemicals/solvents, undesirable byproducts, the toxic/harmful wastes, low efficiency/selectivity, etc. This study represents an attempt to overcome these challenges. To this purpose, biocompatible and highly efficient Ag₂Se quantum dots (QDs) catalysts with antibacterial activity were synthesized in a very rapid (30 sec, rt), simple, inexpensive, sustainable/green, and one-pot strategy in water using ultrasonic irradiation. Characterization of the QDs was performed using different techniques. UV-Vis absorption and fluorescence spectroscopic studies showed an absorption peak at 480-550 nm and a maximum emission peak around 675 nm, which confirmed the successful synthesis of Ag₂Se QDs via the applied biosynthetic method. Subsequently, catalytic reduction of nitroarenes by them was carried out under safe conditions (H₂O, rt, air atmosphere) in ∼ 60 min with excellent yield and selectivity (>99%). Their catalytic activity in the reduction of various toxic nitroarenes to aminoarenes under green conditions was investigated. Thus, a rapid and safe ultrasound-based method was employed to prepare stable and green Ag₂Se QDs phyto-catalysts with unique properties, including exquisite monodispersity in shape (orthorhombic) and size (∼7 nm), air-stability, and good purity and crystallinity. Importantly, instead of various toxic chemicals, the plant extract obtained by rapid ultrasonic method (10 min, rt) was used as natural reducing, capping, and stabilizing agents. Moreover, antibacterial assays results showed that Ag₂Se-QDs catalysts at low concentrations (ppm) have high activity against all tested bacteria, especially E. coli (MIC:31.25 ppm, MBC:125 ppm) which were significantly different from those of Fig extract (MIC = MBC:500 ppm). The data reflect the role of these bio-synthesized Ag₂Se-QDs catalysts in the development of versatile and very safe catalysts with biomedical properties.

Biogenic silver/silver chloride nanoparticles inhibit human cancer cells proliferation in vitro and Ehrlich ascites carcinoma cells growth in vivo

Silver/silver chloride nanoparticles (Ag/AgCl-NPs) were synthesized for the first time from the herbal Geodorum densiflorum rhizome extracts and characterized by different techniques. The surface plasmon resonance peak at 455 nm was observed in the UV–Visible spectrum, the average particle size of 25 nm was determined by SEM, XRD reflection peaks (28.00°, 32.42°, 38.28°, 46.38°, 54.94°, 57.60°, 64.64°, and 67.48°) indicated the presence of Ag-NPs and AgCl-NPs, heat stability was confirmed by TGA and FTIR analysis indicated the presence of alcohol/phenol, alkanes, primary amines, nitro compounds, alkyl chloride functional groups. The synthesized Ag/AgCl-NPs, previously synthesized Kaempferia rotunda and Zizyphus mauritiana mediated Ag/AgCl-NPs separately inhibited the proliferation of BxPC-3 cells with the IC₅₀ values of 7.8, 17.1, and 20.1 µg/ml, respectively. In the case of MCF-7 cells, the IC₅₀ values of G. densiflorum- Ag/AgCl-NPs and K. rotunda-Ag/AgCl-NPs were 21.5 and 23.5 µg/ml, respectively. Whereas the IC₅₀ of G. densiflorum-Ag/AgCl-NPs was 28.0 µg/ml against glioblastoma stem cells (GSCs). Induction of apoptosis in GSCs, BxPC-3 and MCF-7 cells was noted followed by NPs treatment. In GSCs, the expression level of NFκB, TNFα, p21, and TLR9 genes were upregulated after treatment with G. densiflorum-Ag/AgCl-NPs while in the MCF-7 cells, the expression of p53, FAS, Caspase-8 and -9, NFκB, MAPK, JNK and p21 genes were increased. G. densiflorum-Ag/AgCl-NPs inhibited 60% and 95% of EAC cells growth at the doses of 2 and 4 mg/Kg/day after intraperitoneal treatment with five consequent days, respectively. A remarkable improvement of hematological parameters with the decreased average tumor weight and increase of 75% life span of G. densiflorum-Ag/AgCl-NPs treated mice were observed. Altogether, this study reported for the first time in vitro anticancer activity of biogenic G. densiflorum-Ag/AgCl-NPs against GSC cells along with MCF-7 and BxPC-3 cells and in vivo anticancer properties against EAC cells.

Nano-Drug Delivery Systems Entrapping Natural Bioactive Compounds for Cancer: Recent Progress and Future Challenges

Cancer is a prominent cause of mortality globally, and it becomes fatal and incurable if it is delayed in diagnosis. Chemotherapy is a type of treatment that is used to eliminate, diminish, or restrict tumor progression. Chemotherapeutic medicines are available in various formulations. Some tumors require just one type of chemotherapy medication, while others may require a combination of surgery and/or radiotherapy. Treatments might last from a few minutes to many hours to several days. Each medication has potential adverse effects associated with it. Researchers have recently become interested in the use of natural bioactive compounds in anticancer therapy. Some phytochemicals have effects on cellular processes and signaling pathways with potential antitumor properties. Beneficial anticancer effects of phytochemicals were observed in both in vivo and in vitro investigations. Encapsulating natural bioactive compounds in different drug delivery methods may improve their anticancer efficacy. Greater in vivo stability and bioavailability, as well as a reduction in undesirable effects and an enhancement in target-specific activity, will increase the effectiveness of bioactive compounds. This review work focuses on a novel drug delivery system that entraps natural bioactive substances. It also provides an idea of the bioavailability of phytochemicals, challenges and limitations of standard cancer therapy. It also encompasses recent patents on nanoparticle formulations containing a natural anti-cancer molecule.

Anticarcinogenic Potentials of Silver Oxide Nanoparticles Synthesized from Lagerstroemia Indica

In this study, a novel medicinal plant, Lagerstroemia indica, was used to extract Silver Oxide Nanoparticles (Ag2O-NPs) and the in vitro anticancer potentials of synthesized Ag2O-NPs were evaluated on human cancer cell lines. Ultraviolet–Visible (UV-Vis) spectroscopy confirmed the formation of Ag2O and the particle size of 9.98[Formula: see text]nm was confirmed by X-Ray Diffraction (XRD) analysis. Scanning Electron Microscope (SEM) images showed spherical-shaped NPs. The anticancer potential determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay showed significant cytotoxic potential against breast cancer (MCF-7) and cervical cancer (HeLa) cell lines with the IC50 concentrations at 46.22[Formula: see text][Formula: see text]g/ml and 39.39[Formula: see text][Formula: see text]g/ml, respectively. Ag2O-NPs showed a subsequent reduction in Mitochondrial Membrane Potential (MMP) and increased level of Reactive Oxygen Species (ROS). The dual staining of Ag2O-NPs showed a greater number of early apoptotic and late apoptotic cells as compared to the standard drug camptothecin. Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) determined an upregulated level of Caspase3 and p53. Thus, the present study indicates that Ag2O-NPs synthesized from L. indica may be used as an anti-cancer drug after further in vivo trials.

Facile green synthesis of non-genotoxic, non-hemolytic organometallic silver nanoparticles using extract of crushed, wasted, and spent Humulus lupulus (hops): Characterization, anti-bacterial, and anti-cancer studies

Since the last few decades, the green synthesis of metal nanoparticles was one of the most thrust areas due to its widespread application. The study proposed using wasted and unusable Humulus lupulus (Hops) extract to synthesize silver nanoparticles for biomedical application. The environment around us gives us many scopes to use the waste from environmental sources and turn it into something valuable. The spent Hops extract was used to synthesize silver nanoparticles (AgNP@HOPs), and the synthesized product exhibited an excellent therapeutic effect in terms of anti-bacterial and anti-cancer agents. The synthesis was optimized considering different factors like time and the concentration of AgNO₃. The silver nanoparticles were characterized in detail using different characterization techniques XRD, DLS, TEM, BET, XPS, Raman Spectroscopy, SEM, EDAX, AFM, which revealed the uniqueness of the silver nanoparticles. The average hydrodynamic size was found to be 92.42 ± 2.41 with a low polydispersity index. The presence of Ag-C and Ag-O bonds in the AgNP@HOPs indicated that it is composed of organo-silver and silver oxides. The nanoparticles were found to be spherical with an average size of 17.40 nm. The AgNPs were lethal to both E. coli and S. aureus with a MIC-50 of 201.881 μg/mL and 213.189 μg/mL, respectively. The AgNP@HOPs also exhibited an anti-cancer effect with an IC-50 of 147.175. The AgNP@HOPs exhibited less cytotoxicity and genotoxicity against normal cells and exhibited superior haemocompatibility (major criteria for drug selection). There are indeed various reports on the synthesis of silver nanoparticles, but this study proposes a green method for producing non-genotoxic, non-hemolytic organometallic silver nanoparticles using waste material with considerable therapeutic index from the environmental source with potential application in the medical industry. This work could be taken forward for in-vivo studies and for pre clinical studies.

Fabrication and characterization of noble crystalline silver nanoparticles from Pimenta dioica leave extract and analysis of chemical constituents for larvicidal applications

The current works report the bio-efficacy of Pimenta dioica leaf derived silver nanoparticles (Pd@AgNPs) and leaf extract obtained trough different solvents against the larvae of malaria, filarial and dengue vectors. Synthesis of silver nanoparticles (AgNPs) was done by adding 10 ml of P. dioica leaf extract into 90 ml of 1 mM silver nitrate solution, a slow colour change was observed depicting the formation of AgNPs. Further, Pd@AgNPs was confirmed through Ultraviolet–visible spectroscopy which exhibited characteristic absorption peak at 422 nm wavelength. X-ray diffraction and selected area electron diffraction analysis confirmed monodispersed and crystalline nature of Pd@AgNPs with 32 nm an average size. Scanning electron microscopy and transmission electron microscopy showed the most of Pd@AgNPs were spherical and triangular in shape and energy-dispersive X-ray spectroscopy revealed silver elemental nature of nanoparticles. Zeta potential of Pd@AgNPs is highly negative which confirmed its stable nature. Pd@AgNPs showed prominent absorption peaks at 1015, 1047, 1243, 1634, 2347, 2373, 2697 and 3840 cm⁻¹ which are corresponding to following compounds polysaccharides, carboxylic acids, water, alcohols, esters, ethers, amines, amides and phenol, respectively as reported by Fourier-transform infrared spectroscopy analysis. Gas chromatography–mass spectrometry and Liquid chromatography–mass spectrometry analysis revealed 39 and 70 compounds, respectively, which might be contributed for bio-reduction, capping, stabilization and larvicidal behavior of AgNPs. A comparable lethality (LC₅₀ and LC₉₀) was observed in case of Pd@AgNPs over leaf extract alone. The potential larvicidal activity of Pd@AgNPs was observed against the larvae of Aedes aegypti,(LC_50, 2.605; LC_90, 5.084 ppm) Anopheles stephensi (LC_50, 3.269; LC_90, 7.790 ppm) and Culex quinquefasciatus (LC_50, 5.373; LC_90, 14.738 ppm without affecting non-targeted organism, Mesocyclops thermocyclopoides after 72 hr of exposure. This study entails green chemistry behind synthesis of AgNPs which offers effective technique for mosquito control and other therapeutic applications.

Synergistic effect of plant extract coupled silver nanoparticles in various therapeutic applications- present insights and bottlenecks

The phytocomponent conjugated silver nanoparticles (AgNPs) have been extensively explored for various therapeutic applications such as antimicrobial, antioxidant, anticancer, anti-inflammatory, antidiabetic and anticoagulant effects. The bio-conjugation of Ag-based nanomaterial with plant extracts reduces their toxicity to biological systems and enhances their therapeutic effectiveness. The diversity of phytochemicals or capping agents provided by the plant extracts and the small size and large surface area of AgNPs permits maximum adsorption of these capping agents onto their surfaces that further promote the therapeutic performance of phytoconjugated AgNPs in various biomedical applications. The mechanistic action involved in antimicrobial and anticancer functions of AgNPs is mainly dependent on the induction of reactive oxygen species (ROS) resulting in cellular apoptosis and necrosis. This review summarizes the recent studies of various plant extract assisted synthesis of AgNPs, potential biomedical applications with the possible mechanism of action and major shortcomings affecting their therapeutic efficacy.

Efficient and fast degradation of 4-nitrophenol and detection of Fe(III) ions by Poria cocos extract stabilized silver nanoparticles

In this study, a simple and environment-friendly method has been successfully applied for the production of silver nanoparticles (AgNPs) using Poria cocos extract. The reaction time of 60 min, the temperature of 90 °C, and silver ion concentration of 2.0 mM were identified as the best condition for the PC-AgNPs fabrication. The XRD analysis confirmed a highly crystalline face-centered cubic structure of the biosynthesized material. The PC-AgNPs were presented separately in a spherical shape with an average crystal size of 20 nm, as endorsed by the TEM and FE-SEM measurements. The presence and crucial role of biomolecules in stabilizing the nanoparticles were elucidated by FTIR, EDX, and DLS techniques. The prepared biogenic nanoparticles were further applied for the reduction of 4-nitrophenol (4-NP) and colorimetric detection of Fe³⁺ ions. The study results proved that PC-AgNPs exhibited superior catalytic activity and reusability in the conversion of 4-NP by NaBH₄. The complete reduction of 4-NP could be achieved in 10 min with the pseudo-first-order rate constant of 0.466 min^-1, and no significant performance loss was found when the material was reused five times. The colorimetric probe based on PC-AgNPs displayed outstanding sensitivity and selectivity towards Fe³⁺ ions with a detection limit of 1.5 μM in a linear range of 0-250 μM. Additionally, the applicability of the developed assay was explored for testing Fe³⁺ ions in tap water. PC-AgNPs have a great potential for further applications as a promising catalyst for reducing nitrophenols and biosensors for the routine monitoring of Fe³⁺ in water.