Smart Bio-Responsive Hydrogel Incorporating Euphorbia thymifolia L. Extract for Targeted Antimicrobial Release in Chronic Wound Environments

Euphorbia thymifolia L., a lesser-known but pharmaceutically significant medicinal herb from the Chotanagpur Plateau, was investigated for the first time in a smart hydrogel-based delivery system. The hydrogel was formulated using biocompatible polymers and incorporated with ethanolic leaf extract of E. thymifolia, which is rich in flavonoids, alkaloids, and terpenoids. The formulation was designed to respond to pH shifts typically associated with infected wounds (alkaline pH 7.5–8.5), enabling controlled, localised antimicrobial release. Results revealed significant inhibition of Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, demonstrating broad-spectrum antimicrobial efficacy of the hydrogel formulation. A maximum of 88.6% bioactive release was observed under simulated infected conditions (pH 8.5), confirming the system’s responsiveness to alkaline wound environments. This study exemplifies the convergence of traditional phytotherapy and modern biomaterial science in developing sustainable, pH-triggered wound care solutions.