Parikh N H, Porter S C, Rohera B D
College of Pharmacy & Allied Health Professions, St. John's University, Jamaica, New York 11439.
Pharm Res. 1993 Apr;10(4):525-34. doi: 10.1023/a:1018989717297.
Formulation and process variables play an important role in the film-forming properties of coating polymers. Three selected independent coating process variables, namely, percent solids content in the coating polymeric dispersion, inlet-air temperature, and spray rate of the polymeric dispersion, were investigated in this study to determine their effect on the performance characteristics of tablets coated with a plasticized aqueous ethylcellulose dispersion (Sure-lease) in a fluid-bed equipment. Response surface methodology (RSM) was utilized to study the complex relationship between these process variables and selected response variables. Three response variables were considered, namely, rate of drug release from the "untreated" coated tablets and the "thermal-treated" coated tablets and microindentation hardness of the untreated coated tablets. A 12-point factorial experimental design was utilized, and three-dimensional (3-D) response surface plots were generated using a second-order polynomial model. The model provided information needed to predict optimal process conditions. Drug release from the coated tablets followed zero-order kinetics. Inlet-air temperature was found to be the most critical process variable for all the three response variables studied. A correlation was observed between the drug release rate and the microindentation hardness of the applied polymeric coat in the case of untreated coated tablets. The 3-D response surface plots indicated that lower rates of drug release from the coated tablets may be obtained by using high inlet-air temperature and low spray rate of the polymeric dispersion during coating.
配方和工艺变量在包衣聚合物的成膜性能中起着重要作用。本研究考察了三个选定的独立包衣工艺变量，即包衣聚合物分散体中的固体含量百分比、进风温度和聚合物分散体的喷雾速率，以确定它们对在流化床设备中用增塑的乙基纤维素水分散体（Sure-lease）包衣的片剂性能特征的影响。采用响应面法（RSM）研究这些工艺变量与选定响应变量之间的复杂关系。考虑了三个响应变量，即“未处理”包衣片剂和“热处理”包衣片剂的药物释放速率以及未处理包衣片剂的微压痕硬度。采用12点析因实验设计，并使用二阶多项式模型生成三维（3-D）响应面图。该模型提供了预测最佳工艺条件所需的信息。包衣片剂的药物释放遵循零级动力学。发现进风温度是所研究的所有三个响应变量中最关键的工艺变量。在未处理包衣片剂的情况下，观察到药物释放速率与所施加聚合物包衣的微压痕硬度之间存在相关性。三维响应面图表明，在包衣过程中使用较高的进风温度和较低的聚合物分散体喷雾速率，可以使包衣片剂的药物释放速率降低。
