The objective of the study was to reinforce the applicability of the immersion cells for the in vitro release testing (IVRT) of topical formulations by using marketed acyclovir 5% cream formulation (Cream 1) as a model. The method employing the immersion cells was optimized by studying the effect of variables, such as membrane type, media temperature and volume, agitation speed, and cell size, on acyclovir release from the formulation. The in-house formulation similar to the qualitative and quantitative composition of Cream 1 and the other trial formulations with variable compositions were prepared and studied by using the immersion cells. Various other brands of acyclovir topical formulations available in the Indian market were also subjected to IVRT by using the optimized method. An increase in the media temperature from 32°C to 37°C and the stirring speed from 50 to 100 to 150 rpm led to an increase in the drug release. As the immersion cell size increased (0.5, 2 and 4 cm² surface area), the release rate also increased. Nitrocellulose membrane showed the highest drug release and Fluoropore^™the least. The optimized IVRT method could establish the differences in the drug release rates among the formulations with the altered compositions. The method could also prove its discriminatory potential for various marketed formulations. The immersion cell method could serve as a simpler, facile, and reliable aid during product development and also as a quality control tool in assessing stability, aging, and batch-to-batch uniformity of semisolid formulations.

中文翻译：

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使用浸没式细胞对阿昔洛韦局部制剂进行体外释放测试

该研究的目的是加强浸没式细胞在体外的适用性使用市售阿昔洛韦 5% 乳膏制剂（Cream 1）作为模型，对局部制剂进行释放测试 (IVRT)。通过研究诸如膜类型、介质温度和体积、搅拌速度和细胞大小等变量对制剂中阿昔洛韦释放的影响，优化了采用浸没细胞的方法。内部配方类似于 Cream 1 的定性和定量成分以及其他具有可变成分的试验配方，通过使用浸入池进行制备和研究。印度市场上各种其他品牌的阿昔洛韦外用制剂也通过优化方法进行了体外放疗。介质温度从 32°C 增加到 37°C，搅拌速度从 50 到 100 到 150 rpm 导致药物释放增加。²表面积），释放率也增加了。硝酸纤维素膜的药物释放度最高，Fluoropore ^™最低。优化的IVRT方法可以确定具有改变组成的制剂之间的药物释放速率差异。该方法还可以证明其对各种已上市制剂的歧视性潜力。浸入池法可以作为产品开发过程中更简单、简便和可靠的辅助手段，也可以作为评估半固体制剂稳定性、老化和批次间均匀性的质量控制工具。