LAUSR

Graphical abstract Figure. No Caption available. Abstract An amphiphilic chitosan salt, chitosan oleate (CS‐OA), was previously proposed for the physical stabilization of lemongrass antimicrobial nanoemulsions (NE) through a mild spontaneous emulsification process. As both chitosan and oleic acid are described in the literature for their positive effects in wound healing, in the present study CS‐OA has been proposed to encapsulate alpha tocopherol (&agr;Tph) in NEs aimed to skin wounds. A NE formulation was developed showing about 220 nm dimensions, 36% drug loading, and &agr;Tph concentration up to 1 mg/ml. Both CS‐OA and &agr;Tph NE stimulated cell proliferation on keratinocytes and fibroblast cell cultures, and in ex vivo skin biopsies, suggesting the suitability of CS‐OA and of the antioxidant agent for topical application in wound healing. &agr;Tph stability was further improved with respect of encapsulation, by spray drying the NE into a powder (up to about 90% &agr;Tph residual after 3 months). The spray drying process was optimized, to improve powder yield and &agr;Tph recovery, by a design of experiments approach. The powder obtained was easily re‐suspended to deliver the NE and resulted able to completely release &agr;Tph.