Sousa Lobo J M
Centro de Teconologia do Medicamento, Faculdade de Farmácia, Universidade do Porto, Portugal.
Drug Dev Ind Pharm. 2001 Sep;27(8):811-7. doi: 10.1081/ddc-100107244.
Reaching nearly perfect sink conditions is very important in the determination of drug dissolution rates. Many times, the only factor that is taken into consideration in achieving sink conditions is the relation between the drug concentration and its solubility. The analytical conditions of the dissolution assay, as well as the dissolution apparatus, stirring speed, and nature and volume of the dissolution fluid may also influence the dissolution results. The main objective of this work was to study the influence of the stirring rate conditions and of the dissolution apparatus in the diltiazem hydrochloride release from tablets. Diltiazem hydrochloride sustained-release (SR) tablets were tested and the follow ing dissolution parameters were evaluated: t10%, t25%, t50%, dissolution time, mean dissolution time (MDT), and dissolution efficiency (DE) at t120, and at t360. To analyze the release mechanism, several release models were tested, such as Higuchi, zero order, first order, Baker-Lonsdale, Hixson-Crowell, Weibull, and Korsmeyer-Peppas. The similarities between two in vitro dissolution profiles were assessed by the similarity factor f2. The in vitro release kinetics of diltiazem hydrochloride sustained-release tablets were evaluated using the USP 2 (paddle) and USP 4 (flow-through) apparatus.
在药物溶出速率的测定中，达到近乎完美的漏槽条件非常重要。很多时候，实现漏槽条件时唯一考虑的因素是药物浓度与其溶解度之间的关系。溶出度测定的分析条件，以及溶出装置、搅拌速度、溶出介质的性质和体积也可能影响溶出结果。这项工作的主要目的是研究搅拌速率条件和溶出装置对盐酸地尔硫䓬片剂释放的影响。对盐酸地尔硫䓬缓释（SR）片剂进行了测试，并评估了以下溶出参数：t10%、t25%、t50%、溶出时间、平均溶出时间（MDT）以及在t120和t360时的溶出效率（DE）。为了分析释放机制，测试了几种释放模型，如 Higuchi、零级、一级、Baker-Lonsdale、Hixson-Crowell、Weibull 和 Korsmeyer-Peppas 模型。通过相似因子 f2 评估两种体外溶出曲线之间的相似性。使用美国药典2（桨法）和美国药典4（流通池法）装置评估盐酸地尔硫䓬缓释片的体外释放动力学。
