Study on the in Vitro Transdermal Characteristics of Sinomenine Free Base Gel

OBJECTIVE:To investigate the in vitro transdermal characteristics of Simonenine free base gel.METHODS: The transdermal characteristics were evaluated by modified Franz diffusion cell method.Rats'ex vivo skin was used as permeation barrier and the drug concentration was measured by HPLC.RESULTS:The transdermal rate constant(J) of Sinomenine free base was(20.3±3.89) μg·cm-2·h-1,which was 4.72 times that of Sinomenine Hydrochloride.A 5% concentration of 2-pyrrolidone reduced the transdermal delivery of Sinomenine base(P0.05).While compared with the control,the permeation enhancement effects of 5% concentration of Lecithin,Oleic acid,Menthol,Limonene,and Azone were 1.37,2.25,3.71,6.75,and 10.15 times,respectively.CONCLUSION: Compared with Simomenine Hydrochloride,Simomenine free base had excellent transdermal characteristics,and was more suitable for the development of new transdermal preparation.