Valot P, Baba M, Nedelec J-M, Sintes-Zydowicz N
CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Université Lyon 1, F-69622 Villeurbanne, France.
Int J Pharm. 2009 Mar 18;369(1-2):53-63. doi: 10.1016/j.ijpharm.2008.10.037. Epub 2008 Nov 25.
The objective of this study was to obtain an optimum formulation for microencapsulating Ibuprofen. This was achieved by investigating various factors which influenced the microcapsule size. Considering Ibuprofen as a lipophilic model drug, biocompatible Ibuprofen-loaded microcapsules in the size range of 20-60microm were prepared by the water in oil emulsion-solvent evaporation method. An aqueous surfactant phase was used as the continuous external phase (W), a biocompatible organic solvent dissolving Ibuprofen was used as oil phase (O), in addition with a low boiling solvent. The biocompatible polymeric microcapsule membrane was composed of Eudragit RSPO or Ethylcellulose. The influence of various process parameters, such as the volatile organic solvent, the oily core, the stirring rate, on the characteristics of microcapsules was investigated. The encapsulation yield of Ibuprofen close to 100%, whatever the polymer type, was determined by UV-vis experiments, in accordance with the results obtained by (13)C NMR spectroscopy. An innovative technique, DSC-based thermoporosimetry, was used for the estimation of the loading rate of Ibuprofen. The results indicated that this developed analytical method had to be improved since DSC-transitions accounted to free and enclosed Ibuprofen were observed and altered the accuracy of the results.
本研究的目的是获得布洛芬微囊化的最佳配方。这是通过研究影响微囊大小的各种因素来实现的。将布洛芬视为亲脂性模型药物，采用油包水乳液-溶剂蒸发法制备了尺寸范围为20-60微米的生物相容性载布洛芬微囊。水相表面活性剂用作连续外相（W），溶解布洛芬的生物相容性有机溶剂用作油相（O），此外还使用了低沸点溶剂。生物相容性聚合物微囊膜由尤特奇RSPO或乙基纤维素组成。研究了各种工艺参数，如挥发性有机溶剂、油核、搅拌速率对微囊特性的影响。根据(13)C NMR光谱得到的结果，通过紫外-可见实验测定，无论聚合物类型如何，布洛芬的包封率均接近100%。一种创新技术，基于差示扫描量热法的热孔率测定法，用于估算布洛芬的负载率。结果表明，由于观察到差示扫描量热法转变涉及游离和包封的布洛芬，并改变了结果的准确性，因此这种开发的分析方法有待改进。
