不同厂家生产的硝苯地平片体外溶出度的比较

目的：比较国内不同厂家生产的硝苯地平片的体外溶出度。方法：以紫外分光光度法测定硝苯地平的含量,分别根据《英国药典》2010年版、《美国药典》第34版和《中华人民共和国药典》2010年版的方法,对5个厂家生产的硝苯地平片的溶出度进行考察,并比较硝苯地平片在水、pH4.5乙酸钠缓冲液以及pH6.8磷酸盐缓冲液中的溶出度。运用相似因子f2法,比较硝苯地平片在不同溶出介质中溶出曲线的相似性。结果：5个厂家生产的硝苯地平片的溶出度按《中华人民共和国药典》2010年版方法测定,在60min时均〉75%;按《英国药典》2010年版方法测定,45min时均〈75%;按《美国药典》第34版方法测定,20min时均〈80%。以0.1mol/L盐酸溶液为对照,硝苯地平片在人工胃液（不含胃蛋白酶）、水、pH4.5乙酸钠缓冲液和pH6.8磷酸盐缓冲液中的溶出曲线的相似因子f2为50.93～77.45;以0.25%十二烷基硫酸钠溶液为对照,相似因子f2远〈50,表明溶出曲线不相似。结论：5个厂家生产的硝苯地平片的体外溶出度符合《中华人民共和国药典》的要求,但达不到《英国药典》和《美国药典》的标准。国内厂家生产的硝苯地平片溶出度检查标准有待提高。

Comparisons of in vitro dissolution of nifedipine tablets manufactured by different pharmaceutical factories

Objective：To compare in vitro dissolution of nifedipine tablets manufactured by different domestic pharmaceutical factories.Methods：The content of nifedipine was determined by ultraviolet spectrophotometry.The dissolution of nifedipine tablets was determined according to the method specified in Pharmacopoeia of the People＇s Republic of China（ChP,2010 edition）,the United States Pharmacopoeia（USP,34th edition）,and the British Pharmacopoeia（BP,2010 edition）,respectively.And the dissolution was further investigated with water,pH4.5 sodium acetate buffer and pH6.8 phosphate buffer solutions as dissolution media.The similarity of dissolution curves in different dissolution media was compared by using similar factor f2 method.Results：The dissolution of nifedipine tablets from the 5 factories was higher than 75% at 60 min according to the ChP method,lower than 75% at 45 min according to the BP method and far lower than 80% at 20 min according to the USP method.The similar factors f2 were 50.93-77.45 in water,artificial gastric fluid（without pepsin）,pH4.5 sodium acetate buffer and pH6.8 phosphate buffer solutions when 0.1 mol/L HCl solution was used as a reference medium.And the similar factors f2 were far lower than 50 when 0.25% sodium dodecyl sulfate was used as a reference solution.It was indicated that the dissolution curves of nifedipine tablets in these media were different.Conclusion：The dissolution of nifedipine tablets manufactured by the 5 factories meets the requirements of the ChP,but they fail to achieve the USP and BP standards.The dissolution examination standard of nifedipine tablets manufactured by the domestic pharmaceutical factories needs further improvement.