Formulating for Efficacy

The document discussed the importance of delivering active ingredients in cosmetics to the correct location at the right concentration and duration for efficacy. It introduced the relative polarity index, which helps select suitable emollients for effective skin penetration of active ingredients. Practical examples supported this approach, showing that controlling the emollient system can regulate the delivery and efficacy of active molecules in cosmetic formulations. Additionally, experiments suggested that emulsifier systems might influence the targeting of active ingredients to specific skin layers, though general rules could not yet be established.