Green synthesis of alginate-encapsulated silver nanoparticles and its utilization as anticancer and antimicrobial therapeutics

Abstract This study explored the potential of green-synthesized alginate encapsulated silver nanoparticles (AgNPs) for anticancer, antibacterial, and antifungal therapeutic applications. The physicochemical characterization of the biosynthesized nanoparticles was performed using various established techniques. The synthesis of alginate encapsulated AgNPs was confirmed by UV-visible spectroscopy, which showed a peak at ∼450 nm. The SEM images showed an agglomerated structure with an average particle size of 43 nm. Moreover, FTIR analysis displayed a characteristic peaks around 500–700 cm −1 , which are typically associated with Ag–O stretching vibrations, confirming the presence of silver oxide bonds. Furthermore, clear distinct peaks of C, O, Ag and Na were observed in the EDS and corresponding peaks of silver and alginate in X-ray diffraction spectra as well as X-ray photon spectroscopy indicates the purity and crystallinity of the alginate encapsulated AgNPs. The cytotoxicity assay demonstrated a dose-dependent reduction in cell viability of HCT-116 cells with an IC 50 concentration of 28 μg/mL The alginate encapsulated AgNPs was able to induce reactive oxygen species (ROS) production by 22 % and triggered apoptosis by 18 %. Additionally, our biosynthesized AgNPs exhibited significant antimicrobial activity against Pseudomonas aeruginosa , methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter baumannii , and Candida albicans with zone of inhibition (ZOI) of 19.5 mm, 14.5 mm, 17.5 mm, and 16.5 mm, respectively. These findings suggest the potential of our alginate-encapsulated AgNPs, which should be further validated and exploited as multitargeted therapeutics against colon cancer and microbial diseases.