Biofabrication of iron oxide nanoparticles as a potential photocatalyst for dye degradation with antimicrobial activity

Abstract

In the current investigation presented here, avocado fruit rind aqueous extract was exploited to make iron oxide nanoparticles, in a cost competent and eco-cordial method. The Fourier transform infrared analysis exhibited that the phytochemicals which were in the avocado fruit rind acted as biodegradable, stabilizing and reducing agents in the iron oxide nanoparticles biofabrication. The nanoparticles were also tested for their role as a photocatalyst in the decolorization of selective dyes, using a dosage of 20 mg of iron oxide nanoparticles per 50 mL of dye exposed for 5-h sunlight irradiation. The color removal percentage was checked to be at 97, 93, 91, 89 and 82 for the dyes malachite green, Congo red, crystal violet, safranin and methyl orange, respectively. Iron oxide nanoparticles were appraised for their antibacterial response against the scrupulous choice of gram-negative and gram-positive bacteria through agar well diffusion technique. The zone of inhibition was ascertained to be 13, 12, 15, 11, 9, 12 and 14 mm for Escherichia coli, Streptococcus sp., Staphylococcus sp., Salmonella sp., Bacillus sp., Pseudomonas sp. and Proteus sp., respectively, with the aid of 20 µg mL−1 iron oxide nanoparticles. In vitro cytotoxicity of the iron oxide nanoparticles was evaluated on a human cervix epithelial carcinoma cell line, and their inhibitory concentration 50 value was deduced as 381.14 ± 10 µg mL−1. The result serves an allusion data, endorsing the avocado fruit rind sourced iron oxide nanoparticles as relevant agents in applications pertaining to environmental remediation.