Green synthesis of selenium nanoparticles using clove and Thulasi and their antioxidant activity

Abstract

Introduction: Plants have been explored successfully for rapid biosynthesis of metal nanoparticles such as gold, silver, selenium, MgO, CuO, and ZnO nanoparticles. The nanoparticles are used extensively in cancer drug delivery as the drugs bound with nanoparticles can penetrate deep into the organs. Particularly, an essential dietary micronutrient, selenium found in the form of Se NPs, is relatively a new member of drug nanocarriers in medicine because Se NPs exhibit strong antioxidative and anti-bacterial activity.

Aim:   To study the free radical scavenging activity of clove and red tea-mediated zinc oxide nanoparticles using DPPH assay and hydroxyl radical scavenging assay

Materials and methods:

Antioxidant activity:  DPPH assay was used to test the antioxidant activity of biogenic synthesized zinc oxide nanoparticles.

Hydroxyl radical scavenging assay: All solutions were prepared freshly.1.0mL of the reaction mixture contained 100µL of 28mM of  2-deoxy-2-ribose, carcia papaya sol Fecl3 and 1.04mM EDTA,100µL H2O2(1.0mM) and 100µL ascorbic acid.After an incubation period of 1 hour at 37°C the extent of deoxyribose degradation at about 532nm against the blank solution. Vitamin E was used as a positive control.

Result and discussion: The percentage inhibition was only 65% when the concentration was 10 μl, at 20 μl it was 70%, at 30 μl it was 80%, at 40 μl it was 90% and at 50 μl it was 90%. It was observed from the spectra that the extract at 517 nm had the highest radical scavenging activity at a concentration of 50 μl (90%), which is indicative of significant antioxidant activity as potent as DPPH itself. The percentage inhibition was 50% when the concentration was 10 μl, at 20 μl it was 55%, at 30 μl it was 60%, at 40 μl it was 70% and at 50 μl it was 90%. It was observed from the spectra that the extract at 517 nm had the highest radical scavenging activity at a concentration of 50 μl (90%), which is indicative of significant antioxidant activity as potent as hydroxy radical scavenging assay.

Conclusion: In this study, a simple, biological and low-cost approach was done for the preparation of selenium nanoparticles using Tulsi and clove extract. Thus clove and thulasi-mediated selenium nanoparticles can be subjected to various other biological activities such as antibacterial,antifungal, and cytotoxic evaluation to know the efficiency of these nanoparticles.