In vitro evaluation of sustained released matrix tablets containing ibuprofen: a model poorly water-soluble drug

ABSTRACT A matrix system was developed that releases ibuprofen (IB) over a 12-hour period and the influence of the polymer type and concentration on the release rate of the drug was evaluated. Tablets containing different concentrations of Carbopol (CP), hydroxypropyl methylcellulose (HPMC), or ethyl cellulose (EC) were prepared using direct compression and the drug content, content uniformity, hardness, friability, dissolution performance, and in vitro release kinetics were examined. Formulated tablets were found to be within acceptable limits for physical and chemical parameters. The release kinetics of the Carbopol(r)971P 8% formulation showed the best linearity (r 2 =0.977) in fitting zero-order kinetics, suggesting the release rate was time independent. The drug release from tablets containing 8% CP was extended over approximately 18 hours and the release kinetics were nearly linear, suggesting that this system has the potential to maintain constant plasma drug concentrations over 12 hours, which could reduce the frequency of administration and the occurrence of adverse effects associated with repeated administration of conventional IB tablets.

摘要 本研究开发了一种可实现布洛芬（ibuprofen, IB）12小时持续释药的基质给药系统，并考察了聚合物种类与用量对药物释药速率的影响。采用直接压片法制备了分别含有不同浓度卡波姆（Carbopol, CP）、羟丙基甲基纤维素（hydroxypropyl methylcellulose, HPMC）或乙基纤维素（ethyl cellulose, EC）的片剂，对其药物含量、含量均匀度、硬度、脆碎度、溶出性能及体外释药动力学进行了考察。结果显示，所制备的缓释片剂各项理化参数均处于可接受范围内。其中8%浓度卡波姆971P（Carbopol®971P）处方的释药动力学拟合零级动力学方程时线性最佳（决定系数r²=0.977），表明其释药速率与时间无关。含8% CP的片剂药物释药时长可达约18小时，且释药动力学近乎线性，提示该系统可在12小时内维持稳定的血浆药物浓度，从而降低给药频率，同时减少常规布洛芬片剂重复给药所引发的不良反应发生率。