Self-double-emulsifying drug delivery system incorporated in natural hydrogels: a new way for topical application of vitamin C.

This study aimed at the in vitro evaluation of topical hydrogels containing vitamin C-loaded self-double-emulsifying drug delivery system (SDEDDS). The liquid SDEDDS was converted into suitable unmodified xanthan gum hydrogels formulation and the prepared semi-solid hydrogels provided appropriate gel characteristics like pH, viscosity, spreadability, etc. The 5-week storage test displayed that the prepared hydrogels possessed good physicochemical stability. In addition, no significant cytotoxicity to L929 cells was observed for the vitamin C-loaded SDEDDS-based hydrogels, and the prepared hydrogels depicted a sustained drug release over an 8-h period. In vitro permeation study showed that the vitamin C-loaded SDEDDS-based hydrogels could significantly enhance vitamin C retention in the skin and permeation through the skin. The overall results demonstrated that the hydrogels containing vitamin C-loaded SDEDDS could be considered as a promising formulation for topical application.