Effects of Skin Penetration Enhancers in Topical Antiaging Products Containing α-HydroxyAcids and Hyaluronic Acid

Transdermal drug delivery has several advantages and has been vastly investigated over the last decades. Chemical enhancers improve the quantity of drug penetration through the skin. In this study, some conventional solvents and surfactants were used as enhancers to promote dermal penetration of α-hydroxyacids (AHA) and hyaluronic acid (HA). A total of 42 different formulations containing AHA or HA as the active ingredient and a solvent or surfactant as the enhancer were prepared. The experiments for determination of transdermal absorption of AHA or HA for each formulation were performed using a diffusion cell and a slice of chicken skin as model at 32℃. After 1.5 or 12 hours, samples from the medium were collected and analyzed for AHA or HA concentration. After 1.5 and 12 hours, the maximum permeated amount of AHA were 89.8 and 342.5 mg, respectively, which related to the formulations with liquid paraffin. After 1.5 and 12 hours, the maximum permeated amount of HA were 57.3 and 70.6 mg, respectively, which related to the formulations with glycerol. The most effective enhancer for AHA and HA were liquid paraffin and glycerol, respectively. The most effective surfactant for both AHA and HA was Tween 80. The effects of the enhancers were increased by prolonging the exposure time.