Development of Polymeric Nanoparticles Loaded with Phlomis crinita Extract: A Promising Approach for Enhanced Wound Healing.

The use of nanoparticles improves the stability, solubility, and skin permeability of natural compounds in skincare products. Based on these advantages, this study aimed to incorporate the Phlomis crinita extract into polymeric nanoparticles to improve its topical skin delivery for wound healing purposes. The study involved the preparation of nanoparticles of PLGA and PLGA-PEG (PCE-PLGA-NPs and PCE-PLGA-PEG-NPs) using the solvent displacement method, physicochemical and biopharmaceutical characterization, tolerance studies by the HET-CAM assay and evaluation of skin integrity parameters, and in vitro efficacy via a scratch wound healing experiment. The prepared nanoparticles were nanometer-sized with spherical form and demonstrated an encapsulation efficiency greater than 90%. The major component (luteolin) was released following a kinetic model of hyperbola for PCE-PLGA-PEG-NPs and one-phase exponential association for PCE-PLGA-NPs. Moreover, the important permeability of luteolin skin was observed, especially for PCE-PLGA-PEG-NPs. Both formulations exhibited no irritation and no damaging effects on skin integrity, suggesting their safety. Finally, the results of the scratch wound healing experiment using 3T3-L1 cells revealed significant cell migration and proliferation, with an improved efficacy for PCE-PLGA-PEG-NPs compared to the free extract, demonstrating the potential of this formulation in the treatment of wound healing.