Eco-friendly green synthesis of silver nanoparticles utilizing olive oil waste by-product and their incorporation into a chitosan-aloe vera gel composite for enhanced wound healing in acid burn injuries

Abstract

This study focused on the green synthesis of silver nanoparticles (AgNPs) using olive oil waste by-product and their incorporation into Chitosan-Aloe-Vera gel (AgNPs/AV-CS gel). The synthesized AgNPs exhibited a hydrodynamic diameter of 43.78 ± 0.33 nm, polydispersity index (PDI) of 0.073, and a zeta potential of –32.7 ± 0.462 mV. Electron microscopy confirmed the monodispersed and spherical nature of the AgNPs, with sizes ranging from 20 to 25 nm. The green-synthesized AgNPs demonstrated potent antioxidant activity, with inhibition percentages ranging from 82.90 % to 86.73 % and IC50 values of 27.01 ± 0.398 µg/mL, 22.33 ± 0.1414 µg/mL, and 24.35 ± 0.2794 µg/mL for ABTS, DPPH, and H2O2 radicals, respectively. The AgNPs also exhibited significant antimicrobial activity, with minimum inhibitory concentrations (MIC) of 6.25 µg/mL and 9.375 µg/mL against E. coli and P. aeruginosa and MIC of 12.5 µg/mL against S. aureus and S. epidermidis. Moreover, the AgNPs/AV-CS gel formulation demonstrated remarkable wound healing capabilities, achieving a 74.86 % wound contraction by day 7 and complete wound closure by day 21. Histopathological analysis revealed reduced inflammation, extensive fibrosis, and a well-developed dermis with the application of AgNPs/AV-CS gel. Overall, the results suggest that AgNPs/AV-CS gel holds promise as a therapeutic option for acid burn injuries, promoting enhanced wound healing.