Perfluoropolyether phosphate:skin exfoliation after a topical pre-treatment,TEWL and skin elasticity,by in-vivo non-invasive methods

摘要

Glycolic acid(GA)and other alpha-hydroxyacids(AHAs)are common ingredients of products designed to accelerate exfoliation of the skin.It is known that acidic pHs are essential in order to increase the efficacy of AHA-based products.The formulator is,therefore,obliged to achieve a difficult balance between performance(skin exfoliation)and risks(skin irritation).In order to overcome this problem,many common organic acids,and combinations of them,have been proposed,with marginal improvements.The need for a new chemistry,in order to achieve better results,was evident,particularly from the point of view of safety.We decided,therefore,to investigate the efficacy of perfluoropolyether(PFPE)phosphate,a new acidic material,already proposed for lowering the pH without increasing skin irritation.Two gels containing PFPE phosphate at different pH values(3 and 7),an acidic gel containing GA at pH 3,and a neutral gel,without an active compound,were applied on 20 healthy volunteers and evaluated with regard to effects on the skin:Exfoliation after a topical pre-treatment with these gels;Transepidermal water loss(TEWL)and elasticity.The main conclusion of the investigation was that PFPE phosphate has effects,particularly skin exfoliation rate,quite independent of the pH,and comparable to the gel containing GA at pH 3,apparently without the typical drawbacks of AHAs.