Rathod Sudha, Deshpande S G
Indian J Pharm Sci. 2008 Mar-Apr;70(2):193-7. doi: 10.4103/0250-474X.41454.
Pilocarpine nitrate loaded egg albumin microspheres were prepared by thermal denaturation process in the size range of 1-12 mum. A series of batches were prepared to study factors, which may affect the size and entrapment efficiency of drug in microspheres and optimized the process. Drug loaded microspheres so obtained were evaluated for their size, entrapment efficiency, release rate and biological response. Electron photomicrographs were taken (8000X) to study the morphological characteristics of microspheres. The entrapment and encapsulation of pilocarpine after process optimization was found to be 82.63% and 62.5% respectively. In vitro dissolution rate studies revealed that the release of drug from the microspheres followed spherical matrix mechanism. Biological response of microspheric suspension was measured by reduction in intraocular pressure in albino rabbit eyes and compared with marketed eye drops. Various pharmacokinetic parameters viz. onset of action, duration of action, Tmax and AUC were studied. A measurable difference was found in the mean miotic response, duration and AUC of pilocarpine nitrate microspheric suspension.
采用热变性法制备了粒径范围为1 - 12微米的硝酸毛果芸香碱载药白蛋白微球。制备了一系列批次的微球，以研究可能影响微球中药物粒径和包封率的因素，并对工艺进行优化。对所制得的载药微球进行粒径、包封率、释放速率及生物学反应评价。拍摄电子显微镜照片（8000倍）以研究微球的形态特征。工艺优化后，毛果芸香碱的包封率和包裹率分别为82.63%和62.5%。体外溶出速率研究表明，药物从微球中的释放遵循球形基质机制。通过测量白化兔眼内眼压的降低来测定微球悬液的生物学反应，并与市售眼药水进行比较。研究了各种药代动力学参数，即起效时间、作用持续时间、达峰时间和药时曲线下面积。结果发现，硝酸毛果芸香碱微球悬液的平均缩瞳反应、作用持续时间和药时曲线下面积存在显著差异。
