药物熔点测定方法的等效性研究

Equivalence Studies of Different Methods for Drug Melting Point Determination

目的评价药物熔点测定传温液加热法分别通过玻璃液体温度计(A1)和数字温度显示(A2)读取熔点值以及电热块空气加热法(B) 3种方法的熔点测定结果是否存在差异。方法选择5个不同熔点值的化学药品作为目标药物,采用不同品牌的熔点仪测定熔点,结合中国食品药品检定研究院2015～2016年组织实施的化学药品熔点测定能力验证项目的数据,采用等效性检验分析评估A1、A2和B法的熔点测定结果。结果 A1、A2和B法是等效的,三者测定的熔点值不存在显著差异。结论 2015年版《中国药典》"熔点测定法"A法和B法的熔点测定结果无显著差异,A法通过数字温度显示与玻璃液体温度计读取的熔点值无显著差异,本实验为《中国药典》"熔点测定法"中的传温液加热法增加通过熔点仪数字温度显示读取熔点值的相关内容提供了数据支持。

OBJECTIVE To evaluate the equivalence among three different methods for drug melting point determination：（1） method A1 by glass liquid thermometer, （2）method A2 by digital display, and （3） method B by instrumental method. METHODS Five chemical reference substances with different melting points were selected as the target drugs, and different brands of melting point apparatus were used to determine melting point. The apparatus used by method A consists of a glass container for a liquid bath and fitted with a suitable means of heating. The obtained results of the melting point by method A1, A2 and B were evaluated by equivalence testing referring to the data of Proficiency Testing Scheme for the melting point determination of chemical drugs organized by NIFDC in 2015 and 2016. RESULTS Method A1, A2 and B were equivalent,and no significant difference were observed for the melting point values determined by the three methods. CONCLUSION There is no significant difference between the melting point determination method A and method B in the Chinese Pharmacopoeia（ Ch. P）, and the obtained melting point values are equivalent either by glass liquid thermometer or digital display while using method A. This experiment provides scientific data support for potential adoption of digital display in melting point apparatus by Ch. P.