Preparation of drug-in adhesive patches of sinomenine and its in vitro permeability through excised rat skin

Objective To prepare drug-in adhesive patches for sinomenine and evaluate its in vitro transdermal permeability.Methods Drug-in adhesive patches of sinomenine were prepared by dissolving sinomenine and different enhancers into the pressure sensitive adhesive.Permeation characteristics of sinomenine from patches were evaluated using 2-compartment horizontal diffusion cells.Results It was found 87-4098 existed a significant higher flux than 87-2677 on the penetration of sinomenine.The effect of permeation enhancement of different enhancers was in the following order:15%(w) isopropyl myristate10% isopropyl myristate10% Azone5% isopropyl myristate10% oleic acid10% N-methylpyrrolidone.When enhancers were used in combination,the rank order of enhancement effect for sinomenine was 10%(w) isopropyl myristate+5% menthol10% isopropyl myristate+5% Azone10% isopropyl myristate+10% menthol10% isopropyl myristate+10% Azone,however,no synergistic effect was observed compared with 10% isopropyl myristate or Azone alone.Conclusions The drug-in adhesive patches of sinomenine have the potential to become an effective transdermal drug delivery system for curing arthritis deformans and is worthy of further investigation.