소수성 고분자를 방출제어막으로 하는 Reservoir system으로부터의 약물 조절 방출에 관한 연구

Abstract

In an attempt to develop of long-term implantable Drug delivery systems, reservoir type devices with hydrophobic rate limiting membranes were prepared and their drug release kinetics were investigated. Transmembrane permeation studies through the rate limiting membranes were also performed to elucidate the drug release mechanisms. Release controlling agents(RCAs) were employed to control diffusivity through the membranes or drug release from devices. The diffusivity of drug from RCAs dispersed hydrophobic polymer membranes was affected by changing the kind and composition of RCAs. The hydrophobic, hydrophilic balances and degree of disperson of the RCAs in the polymer membranes played an important role in regulating of drug permeability.From polymer matrices coated with hydrophobic polymers drug release was controlled via osmotic pumping mechanism and the pattern of drug release was zero order. Adding RCA in rate limiting polymer membranes resulted in increased release rate of drugs. Changing the kind and composition of RCA, the release rate was regulated. It was founded that the release mechanism of this system showed the zero order kinetics by simple diffusion and osmotic pressure. Applications of these systems as long-term implantable DDS were expected.;Long-term implantable drug delivery system 의 개발을 위해 물리 화학적으로 안정하고 생체적응성이 높은 소수성 고분자인 Ethylene-vinyl acetate copolymer와 Polyurethane Biomer를 활용하여 membrane 및 reservoir type의 정제를 제조하였다. 제조된 device로부터의 약물투과 및 방출은 고분자의 소수성으로 인해 약물사용에 제한점이 있으므로 약물에 대한 확산능조절 및 방출조절을 목적으로 Rate Controlling Agent를 도입하였다. 소수성 고분자막에 RCA를 도입시 약물의 확산능이 증가되었고 RCA의 종류 및 함량을 변화시켜 확산능을 조절하였다. 즉, RCA가 고분자내에서 porous diffusion channel을 형성하는 것으로 사료된다. 한편 lactose tablet에 소수성 고분자를 coating함으로써 osmotic control을 받는 zero order 방출양상을 얻었고, RCA를 혼입하여 방출속도를 증가시켰고 그 종류 및 함량을 변화시켜 방출속도를 조절하였다.