The Inspection In Vitro Release And Quality Evaluation Of Domestic Nitrendipine Tablets

Objective To determine the structure of the unknown impurities in nitrendipine bulk drugs and nitrendipine tablets and impurity of belonging to the related substances and establish nitrendipine miscellaneous mass spectrometry in order to provide a reference basis for quality standard. The purpose is to establish a method that real-time monitoring nitrendipine tablet’s solubility process, inspect the process of digestion in vitro about the preparation of different manufacturers and evaluate preparation’s similarity. Methods Adopting the method which is used to determine related substance about the drug in 2010 edition of Chinese pharmacopoeia and using the method of enrichment and separation to collect relevant material and preliminarily determine the molecular weight and structure of the unknown impurities by LC-MS-MS. We monitored the whole dissolving process of domestic nitrendipine tablets real time by using new FODT-601 type optical fiber drugs solubility real-time measuring instrument which developed by our country independently, we measured nitrendipine tablets from 17 manufacturers and selected the dissolution conditions, determined the dissolution method, selected the reference preparation. We used f2 similar factor method and the AV value method to perform the similar analyzes, compared the difference of dissolution curve with reference preparation. Results The impurity belonging about nitrendipine bulk drugs and nitrendipine tablets is showed through examining related substances for nitrendipine bulk drugs of six factories and nitrendipine tablets of twenty-six factories. At same times, the impurity spectrum was set up. There are differences of dissolution curve between the 17 manufacturers with reference dissolution. And dissolution curve of nitrendipine tablets from different manufacturers have great differences. Conclusion The test results provided important reference for the impurity analysis, the improvement of quality standards and synthesis process about nitrendipine bulk drugs and nitrendipine tablets and provided the test method and judgement basis for the production and drug safety of nitrendipine bulk drugs and nitrendipine tablets. Optical Fiber drugs solubility real-time measuring instrument can determine the dissolution curves of the solid drug in vitro comfortably and accurately. It also can reflect the dissolution of the solid medicament objectively, and be used to evaluate the differences of solid preparation. From studying and comparing the dissolution curve of the nitrendipine tablets we can see that there are large differences of dissolution in vitro of nitrendipine tablets produced by different manufacturers in our country and also shows the risk of differences in efficacy.