Comparison of the characterization and antimicrobial, antioxidant, and in vitro cytotoxic activities of green and chemically synthesized gold nanoparticles

Abstract

AuNPs are produced safely and sustainably using green synthesis techniques, which substitute natural metabolites for hazardous chemicals. The physicochemical, antibacterial, antioxidant, and cytotoxic characteristics of AuNPs were compared after they were produced chemically (CS-AuNPs) and environmentally (GS-AuNPs) utilizing Zingiber officinale extract. The successful synthesis of spherical structures with sizes ranging from 5 to 50 nm was demonstrated by TEM micrographs. The zeta potentials (–26.4 mV and − 17.3 mV for CS-AuNP and GS-AuNP, respectively) explained the high stability. The FT-IR measurements indicated that the AgNPs were coated and stabilized by bioactive chemicals derived from the extract. Gram-positive and gram-negative bacteria were both tested for antibacterial effectiveness. Antioxidant activities were assessed by a free radical scavenging assay. GS-Au NPs at 8x dilution had an 88% DPPH decreasing capacity, while CS-Au NPs at 8x dilution had 73%. The CS-AuNPs and GS-AuNPs displayed a target-oriented effect on MCF7 at lower IC₅₀ concentrations of 100% concentrated and 2-fold diluted compared to the L929 (IC₅₀ value is much more above of 100% concentration for both types of AuNPs). Overall, in comparison to CS-AuNPs, the phytosynthesized GS-AuNPs exhibit broad activities that allow for their usage in a variety of biological and biotechnological applications.