Research On The Structure And Drug Release Mechanism Of An Amphiphilic HMPSA

SIS copolymer, hydrocarbon resin, mineral oil and antioxidants were usually used to prepare hot-melt pressure sensitive adhesives (HMPSA). To develop a novel HMPSA suitable for transdermal delivery system of traditional Chinese medicine, poly (ethyl acrylate-co-methyl methacrylate-co-trimethylammonioethyl methacrylate chloride) (RLPO) and polyethylene glycol 2000 (PEG2000) were introduced into HMPSAs. The phase morphologies of blends were investigated by SEM and AFM. The effect of RLPO and PEG2000 on the compatibility and adhesion property were tested by Differential Scanning Calorimetry (DSC) and CZY-6 holding adhesive testing instrument,respectly. The in vitro drug release experiment was carried out by using Permcell horizontal proliferation system, and the cumulative release percentage was determined by HPLC. The water absorption and solubility were detect.Results:It come into being a bicontinuous structure when SIS:RLPO was 1:2(w/w).The PEG2000 could enhance the compatibility of SIS and RLPO when PEG2000:RLPO was up to 8:10(w/w). The adhesion property comes to the best when PEG2000:RLPO was 8:10(w/w) in the HMPSAs.In the novel HMPSAs, the cumulative release percentage of the hydrophilic drug (geniposide) and lipophilic drug (Oleanolic acid) were 70% and 15%, respectly.Taking into account the water absorption and complement release experiment of geniposide we acquire the conclusion that when PEG2000/RLPO was 8/10and SIS/RLPO was 1/2,the structure was sorption.We also find that the PEG2000 could improve the water absorption of the patch which make the geniposide release faster and the RLPO could control the release of Gardenoside.