Exploring the Therapeutic Properties of Alga‐Based Silver Nanoparticles: Anticancer, Antibacterial, and Free Radical Scavenging Capabilities

The current study was designed to evaluate the antioxidant, anticancer and antimicrobial activities of silver nanoparticles (AgNPs) biosynthesized by Spirulina platensis extract. The biosynthesized silver nanoparticles were characterized using fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X‐ray diffraction (XRD) analysis. The antioxidant activity of the biosynthesized AgNPs were determined via DPPH radical scavenging assay while its anticancer activity was determined using the MTT assay. The antimicrobial activity of the biosynthesized AgNPs were analyzed by disc diffusion method. Spirulina platensis acts as a reducing and capping agent. The biosynthesized AgNPs exhibited strongest antioxidant activities of 80.89 ± 1.99 at 500 g/ml concentration while their lowest antioxidant activities of 36 ± 1.97 were observed at 100µg/ml concentration. MTT results showed that cytotoxicity of biosynthesized AgNPs was concentration dependent (for both HepG2 and A549 cell lines). Furthermore, significant antibacterial activity of the biosynthesized AgNPs was observed against pseudomonas aeroginosa while minimum antibacterial activity was observed against Acetobacter. In conclusion, our biosynthesized AgNPs from the algae Spirulina Platensis can be potent antioxidant, anticancer and antibacterial activities.