RESUMO
The objective of the present study was to establish a method based on principal component analysis (PCA) for the study of transdermal delivery of Chinese medicinal formulae, and to choose the best penetration enhancers for Qingfei Xiaocuo gel depend on this method. Using improved Franz type diffusion cell and excised rat skin in vitro as transdermal barrier, the receptive solution fingerprint was established by HPLC, harvesting the areas of the common peaks in the fingerprint, then the total factor scores of the concentrations at different times were calculated using PCA and were employed instead of the concentrations to compute the cumulative amounts (Q12) and enhancement ratio (ER), the latter of which were considered as the indexes for optimizing penetration enhancers. Compare to the control group, the ER of the other groups increased significantly and furthermore, 2.5% azone with 2.5% menthol manifested the best effect. PCA represent most information in the receptive solution, the method above could choose the best penetration enhancers, it could be a reference for the study of transdermal delivery of Chinese medicinal formulae.