Studies on the properties of ethylcellulose microcapsules prepared by emulsion non-solvent addition method

• Main Authors: Peng Jui Kun, 彭瑞坤
• Other Authors: Chen Hui
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/25369341966233690024

碩士 === 國立中央大學 === 化學工程研究所 === 83 === The preparation of ethylcellulose microcapsules containingheophylline by using o/w emulsion nonsolvent-addition phaseeparation method was developed. Dichloromethane-n-hexane werehosen as solvent-nonsolvent system. The first stage of this workas to determine the process of drug loss. In the second stage ofhis work, some methods were proposed to reduce drug loss. Theharacteristics of microcapsules prepared by these methods werenvestigated. The results indicated that almost drug loss happened in fiveinutes after coating solution was poured into dispersion medium.he drug loss was reduced by increasing the polymer concentration,y adding nonsolvent in coating solution, by using mixed solventnd by adding nonsolvent in the dispersion medium in advance. Theorphology of microcapsules prepared by these methods was alsonfluenced. Dissolution studies showed that the release rate ofheophylline from microcapsules increased with the increase ofolymer concentration, with the increase of the volume of ddition in coating solution, with the increase of the volume ofoluene in mixed solvent and with the increase of the volume ofonsolvent in advance addition in dispersion medium. However, theelease behavior of various ethylcellulose microcapsules fittedhe first order release model and Higuchi matrix release model.