Formulation, Synthesis and Optimization of Dimethyloxalylglycine (DMOG)-Loaded Nanoemulgel for Diabetic Wound Healing

Abstract

Diabetic wounds are characterized by impaired angiogenesis, chronic inflammation, and delayed tissue regeneration, necessitating advanced topical delivery systems capable of sustaining therapeutic action at the wound site. Dimethyloxalylglycine (DMOG), a prolyl hydroxylase inhibitor, enhances hypoxia-inducible factor-1α (HIF-1α) stabilization and promotes angiogenic and collagen-forming pathways; however, its poor aqueous solubility and instability restrict its clinical utility. This study aimed to formulate and optimize a DMOG-loaded nanoemulgel to improve solubility, stability, and controlled release for diabetic wound healing. A Box–Behnken design was employed to evaluate the effects of oil (Capryol 90), surfactant (Tween 80), and co-surfactant (Transcutol P) on encapsulation efficiency, particle size, and in-vitro release. Fifteen formulations were developed, showing encapsulation efficiencies of 84.69–94.02%, particle sizes of 172–223 µm, and cumulative release profiles of 65.7–79.9%. Statistical analysis confirmed the significant influence of oil and surfactant concentrations on all critical responses. Numerical optimization yielded an optimal composition with a desirability value of 0.929, predicting 93.45% encapsulation, 179.39 µm particle size, and 79.9% drug release, which closely matched experimental values (<5% prediction error). The optimized Nanoemulgel was incorporated into a Carbopol 940 gel to obtain a stable nanoemulgel with suitable pH, viscosity, drug content, and spreadability for topical application. In-vitro release followed Higuchi kinetics (R² = 0.983), indicating diffusion-controlled behaviour and sustained delivery. Overall, the DMOG-loaded nanoemulgel demonstrated promising physicochemical and release characteristics, suggesting its potential as an effective topical platform for enhancing diabetic wound healing.