Development and evaluation of a thermosensitive nanoemulsion hydrogel loaded with Schizonepeta annua essential oil for enhanced wound healing

Chronic wounds present a major global healthcare challenge, with bacterial infections significantly impeding healing processes and increasing treatment costs. This study addresses the critical need for multifunctional wound dressings by developing a novel thermosensitive hydrogel incorporating Schizonepeta annua essential oil nanoemulsions (SEO-NE-TG). We hypothesized that this formulation would provide both controlled antimicrobial protection and enhanced tissue regeneration capabilities. Through systematic optimization, we formulated a stable oil-in-water nanoemulsion using Tween-80, achieving uniform nanoparticles (10–20 nm) confirmed by TEM and DLS analysis. The resulting hydrogel demonstrated ideal properties for wound applications, including temperature-responsive gelation (transition at 15.7℃), favorable shear-thinning behavior, and erosion-controlled release of bioactive terpenes. The SEO-NE-TG maintained antimicrobial efficacy against critical wound pathogens including MRSA (MIC 3906 μg/mL), while significantly accelerating wound healing in a rat burn model. Cytotoxicity studies with HaCaT keratinocytes revealed that SEO-NE maintained good biocompatibility at antimicrobial effective concentrations. Treatment resulted in 35 % higher wound contraction rate, enhanced epidermal regeneration, improved collagen organization, and significantly modulated inflammatory markers (IL-6, TGF-β, VEGF) compared to controls. These findings establish SEO-NE-TG as a promising platform for advanced wound management, offering a natural alternative to conventional antimicrobial dressings with superior healing promotion capabilities.