Antimicrobial and cytotoxicity evaluation of Annona muricata-based silver-cobalt nanoparticles on WEHI 164 cell line

The harsh chemicals in conventionally fabricated metal nanoparticles have limited their applications for biomedical purposes. As part of green and sustainable chemistry in this study, an aqueous extract of indigenous Annona muricata was a reductant in preparing silver‑cobalt nanoparticles (Ag Co NPs) for therapeutic application. The reaction progress and rate of formation of nanoparticles were monitored with a UV–visible spectrophotometer. The functional groups, structural morphology, and elemental composition of the Ag Co NPs were confirmed using FTIR, SEM, TEM, and EDX techniques, respectively. This study evaluated the cytotoxicity potential of 21.38 ± 8.0 n m Ag Co NPs on the WEHI 164 cell line for the first time, using an MTT assay and the antimicrobial potential of Ag Co NPs against six microorganisms. The characteristic wavelength of absorption was observed between 400 and 450 nm. The antimicrobial test showed evident growth inhibition by Ag Co NPs on P. aeruginosa, Candida albicans and Aspergillus niger. The in vitro cytotoxicity evaluation on the WEHI 164 cell line indicated that the Ag Co NPs were cytotoxic at an IC 50 dosage of 84 μg/mL, and the cytotoxic potential was concentration-dependent. Hence, the Annona muricata synthesised Ag Co NPs are potential pharmaceutical drug candidates. • Methanol extracted bioactive compounds with stronger intensity than water. • Formation of Ag Co NPs was confirmed by optical and morphological characterisation. • The Ag Co NPs displayed the strongest growth inhibition against Aspergillus niger compared to the control. • Cytotoxicity evaluation of A. muricata -based silver-cobalt nanoparticles (Ag Co NPs) on WEHI 164 cell line for the first time. • The Ag Co NPs are potential antibacterial, antifungal compounds, and anticancer drug candidates in nanomedicine.