药物从赋形剂中释出和穿透到病变部位是皮肤外用药生效的两个要素。体外研究药物经皮吸收通常是用切下的人或动物皮肤,以后发展到用人工膜替代,接受相也由非液体相替代水相,而人工膜则由单层发展到多层膜系统,以便更好地模拟药物从半固体制剂中释出及经皮吸收的情况。 Drug release from the excipient and penetration into the diseased site are two elements of efficacy of the dermal drug. In vitro studies of drug percutaneous absorption is usually cut human or animal skin, later developed to artificial membrane replacement, the accepted phase also replaced the non-liquid phase of the aqueous phase, and the artificial membrane from monolayer to multilayer system, In order to better mimic the release of the drug from the semi-solid formulation and transdermal absorption.