Cheng-ying Shen, Bao-de Shen, Gang Shen, Juan Zheng, Juan-juan Li, Xiao-rong Li, Hong-yan Min, Jin Han*, Hai-long Yuan*

Department of Pharmacy, 302 Military Hospital, Beijing, China,

*Address for correspondence: Jin Han and Hailong Yuan, Department of Pharmacy, 302 Military Hospital, Beijing, China. Tel.:+86 1066933367. Fax: +86 1063879589. Email: yhlpharm@126.com (H. Yuan.); hanjin302emba@163.com (J. Han)

Keywords: Nanosuspension, Drug physicochemical characteristics, Transdermal absorption, Permeation rate, Correlation analysis

Abstract: The purpose of this paper was to study the influence of drug physicochemical characteristics on in vitro transdermal absorption of hydrophobic drug nanosuspensions. Four drug nanosuspensions, which were same in stabilizer and similar in particle size, were produced by high pressure homogenization technique. The results of XRD and DSC showed the crystalline state of the nanocrystals did not change.. In vitro permeation study demonstrated that the permeation rate of drug nanosuspension was higher than that of drug microsuspension. Correlation analysis between drug physicochemical properties and Jss revealed that log P and pKa were factors that influence the in vitro transdermal absorption of hydrophobic drug nanosuspensions and drugs with log P value around 3 and higher pKa value (when pKa < pH+2) would gain higher Jss in this paper.