Changes of Surface Area in the Dissolution Process of Crystalline Substances

概要

論文の詳細を見る
A series of experiments was conducted to evaluate the changes of surface area during the dissolution process of sieved crystalline particles. The dissolution of some paraben derivatives was followed under the sink condition. Whole particles were collected at intervals during the dissolution measurements. The mean diameter and surface area of the gathered particles were estimated by geometrical and projected area measurements on photomicrographs, and with a LUZEX image analyzer. A fairly good correlation between the surface area (S_H) estimated from Heywood's diameter and the projected area was obtained in spite of the gradual change of particle shape. The dissolution rate constants of sieved paraben crystals were very, even though the original particle sizes were different. Dissolution measurements of binary systems mixed at various ratios of the sieved samples were carried out. These dissolution profiles were simulated based on the changes of surface area in the dissolution process of the sieved components by the use of S_H. The simulated dissolution curves estimated from S_H coincided well with those measured over almost the whole dissolution process. The evaluation of dissolution behavior based on the measurement of particle size or particle surface area appears to be useful to estimate or predict the dissolution process.
公益社団法人日本薬学会の論文
1988-07-25