Formulation and Evaluation of Pickering-Type Lipid Emulsions Prepared with a Solid Lipid Nanoparticle Suspension Loaded with a Combretum glutinosum Perr. ex DC. (Combretaceae) Extract: In Vivo Wound Healing Activity

Formulation et évaluation d’émulsions lipidiques de type Pickering préparées à partir d’une suspension de nanoparticules lipidiques solides chargée en extrait de Combretum glutinosum Perr. ex DC. (Combretaceae) : activité cicatrisante in vivo

Résumé

Abstract

Background: Combretum glutinosum is traditionally used in West Africa for wound healing, but the physicochemical instability of its bioactive compounds may limit therapeutic applications. Objective: To develop solid lipid nanoparticles (SLNs) and SLN-based Pickering-type emulsions containing a hydrophilic extract of C. glutinosum and evaluate their wound-healing activity. Methods: SLNs were prepared by hot spontaneous emulsification using Suppocire^® C and Solutol^® HS15. Pickering-type emulsions were formulated with SLN suspensions and an oil phase. Three formulations containing 0%, 0.2%, and 0.8% (w/w) plant extract were evaluated. Wound healing was monitored for 28 days in Wistar rats with second-degree burns using Kamoshida scoring. Results: SLNs exhibited a mean hydrodynamic diameter of approximately 40 nm and spherical morphology. Emulsions showed no macroscopic phase separation over 29 days, although pH increased during storage. Mean wound closure times were 22, 25, and 26 days for formulations containing 0.8%, 0.2%, and 0% extract, respectively. These differences were descriptive and were not statistically tested. Conclusion: SLN-based Pickering-type emulsions offer a promising approach for topical delivery of C. glutinosum extracts. However, encapsulation efficiency remains undetermined, and the observed wound-healing differences require confirmation through adequately powered studies.