Stability of UV Filters in Different Vehicles: Solvents and Emulsions

In this paper, we analyzed the stability of several ultraviolet (UV) filters exposed to simulated solar light. Evaluation of the photostability of UV-A/UV-B filters has an important impact on the efficiency of sunscreen preparations. The purpose of this study is first to relate some of the solvent shifts that can interact with UV filters; secondly, it is to formulate sunscreen emulsions (oil in water and water in oil) in order to evaluate the photostability of sunscreens in the mixture, and therefore their efficiency in solar protection, because photostability and protection are closely linked together.