[In vitro transdermal behavior of effective constituents in Chonghe gel]

Chonghe gel originated from the Chinese ancient prescription, can be used for the treatment of diabetic foot. This experiment was to study the transdermal absorbability of paeoniflorin and osthole in Chonghe gel . Franz diffusing cells method was adopted for the in vitro model of rat belly skins. Paeoniflorin and osthole in the receiving liquid, skins and gel were determined by HPLC. The receiving liquid were screened, and Chonghe gel and Chonghe ointment were compared by transdermal absorbability. Result showed that ethanol-normal saline (2: 8) solution was the appropriate receiving liquid. The penetration rates of paeoniflorin and osthole were 78.07, 7.08 microg x cm(-2) x h(-1). respectively. In 24 h, the accumulated penetration rates were (31.51 +/- 1.33)%, (12.38 +/- 1.28)%, respectively. The retention rates of paeoniflorin and osthole in skin were (0.92 +/- 0.45)%, (4.81 +/- 1.03) %, respectively. The retention of osthole in skins was a drug reservoir. Transdermal behavior of effective constituents in Chonghe gel was more efficient than that in ointment. In vitro, the transdermal behavior of paeoniflorin in Chonghe gel was close to a Weibull process, while the behavior of osthole was close to Higuchi process.