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Background: Recently, researchers are focusing on creating new tools to combat the antibiotic resistant bacteria and malignancy issues, which pose significant threats to humanity. Biosynthesized silver nanoparticles (AgNPs) are thought to be a potential solution to these issues. The biosynthesis method, known for its environmentally friendly and cost-effective characteristics, can produce small-sized AgNPs with antimicrobial and anticancer properties. In this study, AgNPs were bio-fabricated from the distilled water and methanolic extracts of Viburnum grandiflorum leaves. Physio-chemical characterization of the bio-fabricated AgNPs was conducted using UV-visible spectroscopy, scanning electron microscopy, energy dispersive X-ray, and X-ray diffraction analysis. Results: AgNPs produced from the methanol extract were smaller in size (12.28 nm) compared to those from the aqueous extract (17.77 nm). The bioengineered AgNPs exhibited a circular shape with a crystalline nature. These biosynthesized AgNPs demonstrated excellent bactericidal activity against both gram-negative (Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria. Highest antibacterial activity was observed with the methanol extract against P. aeruginosa (14.66 ± 0.74 mm). AgNPs from the methanol extract also displayed the highest antioxidant activity, with an IC50 value of 188.00 ± 2.67 μg/mL against 2,2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, AgNPs exhibited notable cytotoxic activity against Rhabdomyosarcoma cell line (RD cell) of human muscle cancer cell. The IC50 values calculated from the MTT assay were 26.28 ± 1.58 and 21.49 ± 1.44 μg/mL for AgNPs synthesized from aqueous and methanol extracts, respectively. Conclusion: The methanol extract of V. grandiflorum leaves demonstrates significant potential for synthesizing AgNPs with effective antibacterial, antioxidant, and anticancer actions, making them applicable in various biomedical applications. [ABSTRACT FROM AUTHOR]

This study marks a pioneering effort in utilizing Vachellia tortilis subsp. raddiana (Savi) Kyal. & Boatwr., (commonly known as acacia raddiana) leaves as both a reducing and stabilizing agent in the green "eco-friendly" synthesis of silver nanoparticles (AgNPs). The research aimed to optimize the AgNPs synthesis process by investigating the influence of pH, temperature, extract volume, and contact time on both the reaction rate and the resulting AgNPs' morphology as well as discuss the potential of AgNPs in detecting some heavy metals. Various characterization methods, such as UV–vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (IR), Zeta sizer, EDAX, and transmitting electron microscopy (TEM), were used to thoroughly analyze the properties of the synthesized AgNPs. The XRD results verified the successful production of AgNPs with a crystallite size between 20 to 30 nm. SEM and TEM analyses revealed that the AgNPs are primarily spherical and rod-shaped, with sizes ranging from 8 to 41 nm. Significantly, the synthesis rate of AgNPs was notably higher in basic conditions (pH 10) at 70 °C. These results underscore the effectiveness of acacia raddiana as a source for sustainable AgNPs synthesis. The study also examined the AgNPs' ability to detect various heavy metal ions colorimetrically, including Hg2+, Cu2+, Pb2+, and Co2+. UV–Vis spectroscopy proved useful for this purpose. The color of AgNPs shifts from brownish-yellow to pale yellow, colorless, pale red, and reddish yellow when detecting Cu2+, Hg2+, Co2+, and Pb2+ ions, respectively. This change results in an alteration of the AgNPs' absorbance band, vanishing with Hg2+ and shifting from 423 to 352 nm, 438 nm, and 429 nm for Cu2+, Co2+, and Pb2+ ions, respectively. The AgNPs showed high sensitivity, with detection limits of 1.322 × 10–5 M, 1.37 × 10–7 M, 1.63 × 10–5 M, and 1.34 × 10–4 M for Hg2+, Cu2+, Pb2+, and Co2+, respectively. This study highlights the potential of using acacia raddiana for the eco-friendly synthesis of AgNPs and their effectiveness as environmental sensors for heavy metals, showcasing strong capabilities in colorimetric detection. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have been widely studied due to their interesting physicochemical properties and remarkable antibacterial properties. Chemical synthesis methods, including green chemistry, have achieved 0D nanostructures. However, ecological methods have little studied self-assembling Ag nanostructures, such as flowers or dendrites. In this work, Ag dendrites and Ag flower-like morphologies have been successfully synthesized using a one-step green method employing Arctostaphylos pungens Kunth fruit extract at room temperature. The antibacterial properties of both nanostructures were evaluated against Gram-positive Escherichia coli and Gram-negative Staphylococcus aureus bacteria. Scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–Vis), and infrared spectroscopy (IR) characterized the synthesized products. The morphological changes of the nanostructures come from the variation in the concentration of the precursor salt, silver nitrate (AgNO3). A growth mechanism is proposed that includes the formation of nanospheres and their subsequent transformation into Ag dendrites. Both nanostructures show good antibacterial activity against the tested microorganisms. The Ag dendritic nanostructures presented inhibition zones of 11 mm and 10.7 mm against Escherichia coli and Staphylococcus aureus bacteria. However, the flower-like structure was slightly less effective, presenting 11 and 9.5 mm inhibition zones against the same microorganisms, respectively. [ABSTRACT FROM AUTHOR]

The fluorescent silver nanoparticles were synthesized using trisodium citrate as a reducing and stabilizing agent in a microwave-assisted reduction process. The influence of synthesizing parameters such as reaction duration, temperature, and trisodium citrate concentration (100, 200, and 400 ppm) were examined on the characteristics and fluorescent properties of synthesized silver nanoparticles (AgNPs). The formation of AgNPs was studied by UV–Vis absorption spectroscopy, X-ray diffraction, ATR-FTIR spectra, and scanning electron microscopy. The low concentration compared to the high concentration of trisodium citrate resulted in a prolonged reduction process, and also the high concentration resulted in the formation of smaller AgNPs (44 nm). The fluorescence emission spectra of the synthesized colloidal AgNPs demonstrated a quite explicit emission peak centered around 335 nm. However, the higher reaction temperature (above 100 °C) resulted in a sharp and narrow emission peak. The synthesized silver nanoparticles exhibited a suitable fluorescent property, which was reliant on the size of synthesized AgNPs. [ABSTRACT FROM AUTHOR]

In this study, we aimed at the green synthesis of silver nanoparticles (AgNPs) using Lavandula angustifolia extract and the investigation of the anti-proliferative and apoptotic inducing effects of these nanoparticles in the U87MG glioblastoma cancer cell line. Green synthesized silver nanoparticles were characterized by various analytical techniques such as UV–Visible Spectrophotometer (UV–Vis), scanning electron microscopy (SEM) and Energy Dispersive X-ray (EDX). UV–Vis spectroscopy displayed a specific silver plasmon peak at 430 nm. U87MG cells were treated at increased concentrations with Lavandula angustifolia-AgNPs (La-AgNPs) (0–20 µg/mL) for 72 h and the anti-proliferative effects of green synthesized silver nanoparticles on U87MG cells were evaluated by MTT assay. The La- AgNPs induced a statistically significant dose-dependent decrease in proliferation and increased cytotoxicity in U87MG cells. The IC50 value is 7.536 µg/mL. Furthermore, the expression of apoptosis proteins caspase-3, caspase-8 and caspase-9 was analyzed using ELISA and caspase-3 and p53 using western blotting. The results suggest that La-AgNPs induce cell death in U87MG cells through the p53 mediated intrinsic apoptotic pathway. Together, the present findings suggest that La-AgNPs could be considered as a potential option for the treatment of glioblastoma. [ABSTRACT FROM AUTHOR]

In this study, we aimed at the green synthesis of silver nanoparticles (AgNPs) using Lavandula angustifolia extract and the investigation of the anti-proliferative and apoptotic inducing effects of these nanoparticles in the U87MG glioblastoma cancer cell line. Green synthesized silver nanoparticles were characterized by various analytical techniques such as UV–Visible Spectrophotometer (UV–Vis), scanning electron microscopy (SEM) and Energy Dispersive X-ray (EDX). UV–Vis spectroscopy displayed a specific silver plasmon peak at 430 nm. U87MG cells were treated at increased concentrations with Lavandula angustifolia-AgNPs (La-AgNPs) (0–20 µg/mL) for 72 h and the anti-proliferative effects of green synthesized silver nanoparticles on U87MG cells were evaluated by MTT assay. The La- AgNPs induced a statistically significant dose-dependent decrease in proliferation and increased cytotoxicity in U87MG cells. The IC50 value is 7.536 µg/mL. Furthermore, the expression of apoptosis proteins caspase-3, caspase-8 and caspase-9 was analyzed using ELISA and caspase-3 and p53 using western blotting. The results suggest that La-AgNPs induce cell death in U87MG cells through the p53 mediated intrinsic apoptotic pathway. Together, the present findings suggest that La-AgNPs could be considered as a potential option for the treatment of glioblastoma. [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles (AgNPs) using a number of biological agents such as extracts from various parts of the plants have garnered remarkable attention recently. The aim of the study was a green synthesis of AgNPs using stems and flowers of Felty germander (Teucrium polium L.). After collection and preparation of the aqueous extract, production of AgNPs was performed. In the study, effect of parameters including AgNO3 concentration (1, 5, 10, 15, 20, 25, and 50 mM), aqueous extract (100 µl, 150 µl, 300 µl, 600 µl and 900 µl), pH value (between 0 and 14), incubation time (5, 10, 15, 20, 25, and 30 min), and temperature (30 °C, 60 °C, and 90 °C) were investigated in the synthesis of AgNPs. The sufficient production was achieved at the room temperature (30 °C), duration of 15 min, pH of 6 and concentration of 7.5 mM of AgNO3. Finally, the antifungal activity of these nanoparticles was also studied on Fusarium oxysporum by colony formation assay. The production of AgNPs was identified by an absorption peak at approximately 450 nm using UV–Visible spectroscopy. According to XRD, DSL, FESEM, and PSA results and analysis of SEM, nanoparticles have almost spherical shape and size of 10 to 100 nm. The SEM images also revealed that the prepared AgNPs are particles with no agglomeration. Furthermore, the TEM images exhibited that the AgNPs were well dispersed and there was no evident aggregation. Absorption peaks at 3391.55, 2917.00, 2848.83, 1640.15, 1384.65, 1243.37, 1069.07 and 614.54 cm−1 were observed for the AgNPs using FTIR analysis. On the other hand, the antifungal analysis revealed that these AgNPs have antifungal activity. For the first time, the biosynthesis of AgNPs was successfully performed using the aqueous extract of Felty germander which is a rapid, inexpensive and safe approach. Furthermore, the resulting AgNPs has antifungal activity. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles was synthesized by a simple and ecofriendly method using plant gums of Araucaria heterophylla, Azadirachta indica and Prosopis chilensis. The biosynthesised silver nanoparticles were characterized by UV–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive spectroscopy, Dynamic light scattering etc. Silver nanoparticles were tested for its antibacterial activity against Escherichia coli and Streptococcus sp. and anticancer activity against human breast cancer cell line (MCF 7) and also utilized for chromium removal. The particles were found to have antibacterial activity. [ABSTRACT FROM AUTHOR]

Hydrogels were synthesized by grafting polyacrylamide onto dextran using N,N′-methylene-bis-acrylamide as a cross-linker. The hydrogels were converted into polyelectrolytes by alkaline hydrolysis, and samples having various concentrations of ionic groups were obtained. The swelling behavior of the hydrogels in distilled water at room temperature was studied. Silver nanoparticles were generated in situ into the hydrogel network by silver ion reduction with ultraviolet (UV) irradiation. A series of hydrogel–silver nanoparticle composites synthesized in cross-linked polymer matrix with various degree of hydrolysis were characterized by Fourier-transform infrared (FTIR) spectroscopy, UV–Vis spectroscopy, and scanning electron microscopy. The absorption bands indicated formation of polydisperse Ag nanoparticles of 20, 50, and 100 nm in size. The FTIR spectrum of the hydrogel confirmed a weak interaction between –NH2 groups of polymer chains and Ag nanoparticles that stabilizes the nanosystems. It was shown that such hydrogel matrices can be used as effective nanoreactors for synthesis of silver nanoparticles. The size of the nanoparticles depends on the degree of hydrolysis of the polyacrylamide as well as the irradiation time of the silver ions incorporated into the polymer matrix. [ABSTRACT FROM AUTHOR]

An eco-friendly, green synthesis of silver nanoparticles (SNPs) employing the fruit extract of Bridelia retusa was investigated. The UV-visible spectrum showed the surface plasmon peak at 436 nm, a characteristic feature of SNPs. SEM image showed spherical nanoparticles and EDX evidenced the presence of metallic silver with a strong signal for silver atoms at 2.98 keV. XRD patterns verified the crystalline nature of the SNPs which depicted a sharp peak at 38.52° corresponding to (111) plane and the average crystallite size was determined as 22.48 nm. Fourier Transform Infrared spectroscopic analysis confirmed the role of phenolic compounds in the synthesis and stabilization of nanoparticles. The average hydrodynamic diameter of the nanoparticles was 68.49 nm and their polydispersity index was 0.171 which corroborated the monodispersity. A high negative zeta potential value (−27 mV) provided the stability to the colloidal nanoparticle solution. The accelerated reduction of the Congo red dye in the presence of SNPs with a degradation rate constant of 0.056 min confirmed the catalytic potential of nanoparticles. Moreover, the synthesised nanoparticles inhibited the formation of blood clots in human blood samples which proved the anticoagulant activity and hence the nanoparticles can be used in nanomedicine. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) was synthesized by using AgCl precursor with the stabilizing agent Cissus quadrangularis by precipitation method and the obtained particles were characterized by X-ray diffraction (XRD) analysis, Field Emission Scanning Electron Microscope (FESEM) and UV-Visible (UV-Vis) analysis. The influence of a stabilizing agent on AgNPs was compared with non-stabilized AgNPs through the experimental analysis. The XRD patterns show pure face center cubic structure for both samples, whereas the crystallite size is found to be low in stabilizer used samples. FESEM image and the UV-Vis spectra show less agglomeration and blue shift respectively, for stabilizer used AgNPs, indicating small size particles. Photoluminescence spectra show the emission band at 390 nm for both samples. Antibacterial tests show good activity against Pseudomonas aeruginosa for stabilizer used AgNPs. The study concluded that Cissus quadrangularis can be used as a potential stabilizing agent for preparing AgNPs from AgCl, for optical and biomedical applications. [ABSTRACT FROM AUTHOR]