Aloe vera leaf extract as a sustainable route for silver nanoparticle synthesis with enhanced antimicrobial activity

This study shows how to easily make silver nanoparticles (AgNPs) using Aloe vera leaf extract a simple and green approach. This method offers a biocompatible, economical, and environmentally friendly method without hazardous chemicals. A central composite design (CCD) was used to find the best way to make nanoparticles, adjusting the amount of AgNO₃, the pH, and the incubation time to see how they all worked together. Samples of the mixture were taken every hour to track the development of nanoparticles using the UV-Vis spectrophotometer. The reaction mixture gradually turned from white to a reddish-brown hue within the first 5 to 10 min, signaling the formation of AgNPs. We found that using 2.2185 mM of AgNO₃, a pH of 11.91, and a 2.91-h incubation period produced the most AgNPs. Further tests, including UV-Vis spectroscopy, DLS, XRD, FTIR, SEM, and DSC, showed that these nanoparticles were generally spherical, with an average size of 68.79 nm. The sample also had a good PDI of 0.374, and the powder was mostly made up of a highly crystalline Ag-3C silver phase (70.8%). Antimicrobial studies revealed that the synthesized AgNPs exhibited significant inhibitory activity against Salmonella thypae, This research shows that Aloe vera leaf extract can be used to create AgNPs in an environmentally friendly way. These AgNPs show promise for fighting bacteria like E. coli and Staphylococcus aureus, as well as the fungus Aspergillus niger.