Objective: To compare in vitro permeation behavior differences between Qingfang Zhongtong external application powder and gel. Method: Taking transdermal diffusion instrument

with sinomenine as index component

abdominal skin of wistar rats containing cuticular as permeability medium

percutaneous penetration content of sinomenine in Qingfang Zhongtong external application powder and gel at seteing times were determined by HPLC

mobile phase was methanol-water-ethylene diamine (50:50:0.1)

detection wavelength was 262 nm

in vitro permeation behavior of these two formulations was compared. Result: Cumulative penetration content of Qingfang Zhongtong external application powder and gel were 0.405 24

0.191 14 mg·cm-2 in 12 hours

respectively.Cumulative penetration percentage of them were 74.52% and 35.15%

respectively.Penetration behavior of sinomenine in these two formulations conformed to Higuchi equation

transdermal rate were 0.180 5

0.073 4 mg·cm-2·h-1

respectively. Conclusion: Both Qingfang Zhongtong external application powder and gel have sustained release effect.The gel releases drugs much more quickly at an early period

but during whole process of percutaneous penetration

external application powder can significantly improve both cumulative penetration content and transdermal rate of sinomenine.