Controlled Release of Drugs from Silicone Rubber Matrices-Effects of Physical Properties of Drugs and Release Controlling Agents on Drug Release Mechanisms-

실리콘 마트릭스로부터의 약물조절 방출-약물 및 방출조절제의 물성이 방출기전에 미치는 영향-

Matrix type silicone rubber devices were designed for long-term implantable drug delivery system. Release controlling agents (RCA), i.e., polypropylene glycol, polyethylene glycol, were employed to control drug release from the devices. The release rate of drug from RCA dispersed silicone matrices was mainly dependent on hydrophilicity-hydrophobicity of drug and RCA. In the case of hydrophilic drug, the release from the RCA dispersed matrix was regulated by swelling kinetics. Especially when the relatively hydrophobic polypropylene glycol was used, swelling control mechanism induced zero-order release kinetics. Whereas, the release of hydrophobic drug was resulted from partition mechanism. The effect of RCA was to increase drug diffusivity.