Harnessing Pomegranate Peel for One-Pot Synthesis of Zinc-Strontium Nanoparticles: A Natural Antioxidant Nanoplatform

Abstract

Background: Zinc–strontium nanoparticles (Zn–Sr NPs) are emerging as potent antioxidant nanomaterials with potential biomedical applications. Green synthesis using plant extracts offers an eco-friendly and sustainable approach, incorporating bioactive phytochemicals that enhance nanoparticle functionality and biocompatibility.

Objective: To synthesize Zn–Sr NPs using pomegranate (Punica granatum) peel extract via a one-pot method and evaluate their in vitro antioxidant activity.

Materials and Methods: Fresh pomegranate peels were washed, shade-dried, and ground into a fine powder. An aqueous extract was prepared by heating the powder in distilled water, followed by filtration and centrifugation. Zn–Sr NPs were synthesized by mixing 50 mL of the extract with 50 mL of 0.1 M solutions of zinc nitrate and strontium nitrate under continuous stirring at 80°C for 2 hours. The nanoparticles were purified, dried at 60°C, and assessed for antioxidant activity using the DPPH radical scavenging assay at concentrations of 20–80 µg/mL. L-ascorbic acid served as the standard for comparison.

Results: The biosynthesized Zn–Sr NPs exhibited concentration-dependent antioxidant activity, with DPPH inhibition of 20.05%, 27.42%, 35.00%, and 37.80% at 20, 40, 60, and 80 µg/mL, respectively. L-ascorbic acid showed inhibition of 31%, 30%, 37%, and 48% at the corresponding concentrations. The radical scavenging potential of Zn–Sr NPs is attributed to the synergistic effects of zinc and strontium ions and surface-bound phytochemicals from the pomegranate extract.

Conclusion: Pomegranate peel–mediated Zn–Sr NPs can be efficiently synthesized via a green one-pot approach and exhibit significant antioxidant activity. These findings highlight their potential as sustainable, biocompatible nanoplatforms for biomedical and pharmaceutical applications, particularly in mitigating oxidative stress.