热重/差热分析法鉴别车前子和葶苈子的研究

Identification of Plantaginis Semen and Descurainiae Semen by Themogravimetric/Differential Thermal Analysis

目的:为了建立一种快速鉴别中药材车前子和葶苈子的手段,采用热重-微分热重(TG-DTG)和差热分析(DTA)方法对车前子和葶苈子进行热分析研究。方法:以α-Al2O3为参照物,N2为气氛的条件下,升温速率为10℃·min^(-1),温度变化范围为30～600℃,对车前子和葶苈子的热分析图谱进行比较鉴别。结果:车前子和葶苈子的TG-DTG和DTA图谱中峰形存在差异,易于区分,其中车前子和葶苈子的TG曲线分别呈现出1个和2个拐点,而它们的DTA曲线分别呈现出1个较为明显的放热峰和1个较为平缓的放热峰。结论:试验表明热分析法具有操作简便、测量快速、谱图易解析和试剂用量少等好处,可以作为一种快速鉴别车前子和葶苈子的手段。

Objective:To establish a rapid analysis method of identifying Plantaginis semen and Descurainiae semen,by themogravimetric-differential themogravimetric analysis(TG-DTG)and differential themogravimetric analysis(DTA).Methods:The two herbs were identified by comparing differences of chromatography under N2condition,α-Al2O3 as the reference substance,the velocity of rising temperature with 10℃·min^-1 from 30℃to 600℃.Results:The TG-DTG and DTA chromatographies of Plantaginis Semen and Descurainiae Semen were different in peak shape,which was easy to distinguish.Among them,the TG curves of Plantaginis Semen and Descurainiae Semen exhibited one and two inflection points respectively,and their DTA curves showed one steep exothermic peak and one gradual exothermic peak.Conclusion:There are many advantages in applying thermal analysis,such as tiny reagent consumption and simple analysis,which is a rapid,simple and convenient method to identify Plantaginis Semen and Descurainiae Semen.