Development and in vitro evaluation of reservoir-type patch of coumarins in Angelicae Dahuricae Radix / 中草药

ABSTRACT

Objective To prepare the reservoir patch of coumarins in Angelicae Dahuricae Radix and investigate its release and transdermal absorption characteristics in vitro. The efficient enhancers were chosen to improve the drug’s permeation rate. Methods The reservoir patch was prepared using hydroxypropyl methylcellulose (HPMC) as medium and ethylene vinyl acetate (EVA) membrane to control the release of drug. The Franz diffusion cells were used and HPLC was used to determine imperatorin content and permeation rate. The content of imperatorin was determined by HPMC. The effect of the gel consumption, the content of coumarins and penetration enhancer on the transdermal flux were investigated by selecting porcine skin as model. The release of the selected patch in vitro was investigated. Results 1% HPMC, 1% coumarins in Angelicae Dahuricae Radix, 1% Isopropyl Myristate (IPM) and 3% Azone were the best permeation of the patch. The permeation rate reached 0.713 μg/(cm2•h). The release mechanisms of the patch in vitro coincided with zero-order kinetic. Conclusion The reservoir patch of coumarins in Angelicae Dahuricae Radix had high transdermal rate and complete in vitro release. It was indicated that the patch could be expected to be an effective transdermal drug delivery system.