Evaluation of Anticancer activity of Silver Nanoparticles on the A549 Human lung carcinoma cell lines through Alamar Blue Assay.

Silver nanoparticles have been widely studied to possess antimicrobial as well as anticancer activity, and have found its applications in various fields including pharmaceutical industry, diagnostics, drug delivery, food industry, and others. For this purpose, several cell proliferation assays are widely used for the evaluation of anticancer activity of synthetic compounds as well as natural plant extracts. In general, a compound is said to possess an anticancer activity if it prevents the cancer cells to grow and divide actively, and indirectly activates the generic program of cell death. In this protocol, Alamar blue and MTT assay are described for the analysis of metabolic function and health of the cell. These procedures are generally used for the endpoint analysis. A549 cells are seeded in a 96-well plate, and after the adherence of the cells, they are treated with different concentrations of silver nanoparticles. Followed by 24 h of incubation, colorimetric dyes are added to the wells, and the absorbance is recorded to quantify the percentage cytotoxicity in the sample wells.

Catalytic, antibacterial and antibiofilm efficacy of biosynthesised silver nanoparticles using Prosopis juliflora leaf extract along with their wound healing potential.

The present study focuses on the catalytic, antibacterial and antibiofilm efficacy of silver nanoparticles (AgNPs) in an easy, rapid and eco-friendly pathway. Herein, we have synthesised AgNPs using an aqueous extract of P. juliflora leaf. The bioactive compounds present in the extract are responsible for the reduction of Ag+ to Ag0. The particle synthesis was first observed by visual color change and then characterized using UV-visible spectroscopy to confirm the formation of AgNPs. The synthesis conditions were then optimised using critical parameters such as reaction time, AgNO3 concentration, extract to AgNO3 ratio and temperature of the reaction. The hydrodynamic size of the AgNPs with Dynamic light scattering (DLS) was 55.24 nm, while, was in the range of 10-20 nm as determined through Transmission Electron Microscopy (TEM). Further, Fourier transform infrared spectroscopy (FTIR) studies were conducted to discern the functional groups or compounds responsible for the reduction of silver nitrate as well as the capping of silver nanoparticles. Later, X-ray diffraction (XRD) results showed crystalline nature of the biosynthesized AgNPs. To evaluate their antibacterial potential, AgNPs were assessed through disc-diffusion assay, which resulted in an appreciable dose-dependent activity. The antibacterial potential was investigated through disc-diffusion assay against E. coli and P. aeruginosa. The Congo red agar (CRA) plate assay successfully revealed the anti-biofilm activity against B. subtilis and P. aeruginosa. Further, the catalytic activity of synthesised AgNPs was assessed against azo dyes such a Methylene Blue (MB) and Congo Red (CR) that resulted in its effective degradation of toxic compounds in a short span of time. Further, AgNPs were assessed for their wound healing potential.

Green synthesis of silver nanoparticles using Prosopis juliflora bark extract: reaction optimization, antimicrobial and catalytic activities.

In the present study, silver nanoparticles (PJB-AgNPs) have been biosynthesized employing Prosopis juliflora bark extract. The biosynthesis of silver nanoparticles was monitored on UV-vis spectrophotometer. The size, charge and polydispersity index (PDI) of PJB-AgNPs were determined using dynamic light scattering (DLS). Different parameters dictating the size of PJB-AgNPs were explored. Nanoparticles biosynthesis optimization studies suggested efficient synthesis of highly dispersed PJB-AgNPs at 25 °C when 9.5 ml of 1 mM AgNO3 was reduced with 0.5 ml of bark extract for 40 min. Characterization of PJB-AgNPs by SEM showed spherical-shaped nanoparticles with a size range ∼10-50 nm along with a hydrodynamic diameter of ∼55 nm as evaluated by DLS. Further, characterizations were done by FTIR and EDS to evaluate the functional groups and purity of PJB-AgNPs. The antibacterial potential of PJB-AgNPs was tested against E. coli and P. aeruginosa. The PJB-AgNPs remarkably exhibited anticancer activity against A549 cell line as evidenced by Alamar blue assay. The dye degradation activity was also evaluated against 4-nitrophenol that has carcinogenic effect. The results thus obtained suggest application of PJB-AgNPs as antimicrobial, anticancer and catalytic agents.

Antibacterial potential of silver nanoparticles biosynthesised using Canarium ovatum leaves extract.

Silver nanoparticles (AgNPs) have been extensively used as antibacterial agents, owing to their ease of preparation. In the present study, leaves extract of Canarium ovatum have been employed for the biosynthesis of silver nanoparticles (CO-AgNPs). CO-AgNPs were synthesised under very mild, eco-friendly manner where the plant extract acted both as reducing and capping agent. These AgNPs were synthesised by taking into account several parameters, that included, time of reaction, concentration of AgNO3, amount of extract and temperature of reaction. The optimisation studies suggested efficient synthesis of CO-AgNPs at 25°C when 1.5 mM AgNO3 was reduced with 1:20 ratio of plant extract for 40 min. Size determination studies done on dynamic light scattering and scanning electron microscope suggested of spherical shape nanoparticles of size 119.7 ± 7 nm and 50-80 nm, respectively. Further, characterisations were done by Fourier transform infrared and energy-dispersive X-ray spectroscopy to evaluate the functional groups and the purity of CO-AgNPs. The antibacterial efficacy of CO-AgNPs was determined against the bacterial strain Pseudomonas aeruginosa. As evident from disc diffusion method studies, CO-AgNPs remarkably inhibited the growth of the tested microorganism. This study suggested that C. ovatum extract efficiently synthesises CO-AgNPs with significant antibacterial properties and can be good candidates for therapeutics.

Degradation of anthropogenic pollutant and organic dyes by biosynthesized silver nano-catalyst from Cicer arietinum leaves.

The work represents the potent catalytic activity of silver nanoparticles synthesized from Cicer arietinum (chickpea) leaf extract (CAL-AgNPs). Here, silver nano-catalysts were used against the anthropogenic pollutants mainly involving nitro-amines and azo dyes. These pollutants are extremely harmful to our environment and causes severe health issues. The CAL-AgNPs have the potential to degrade harmful toxins and their by-products, thereby decreasing the pollutants from the environment. The green synthesis of nano-catalyst includes a simple, cost effective and eco-friendly method using the leaf extract from the plant. A systematic study was conducted, including synthesis, optimization and characterization of the silver particles. The AgNPs were further assessed through DLS and TEM for size and morphological evaluation. The obtained particles have shown spherical morphology with the size range of 88.8nm. Further, FTIR were performed for compositional and functional group analysis of the particles. The antibacterial efficiency was also evaluated against E. coli and P. aeruginosa. For their catalytic evaluation, CAL-AgNPs were assessed for 4-nitrophenol, methylene blue and congo red. The results obtained through catalytic evaluation suggested that the CAL-AgNPs could be helpful to surmount the environmental pollution in a very effective manner.