艾绒混伪品鉴别方法

Identification of Moxa Floss Adulterant

目的:通过对艾绒的薄层色谱鉴别,气相色谱-质谱联用(GC-MS)成分分析,初步建立艾绒混伪品的鉴别方法。方法:将正品艾绒、混伪品艾绒加石油醚(60~90℃)加热回流,蒸干后加环己烷溶解作为供试品溶液,另取艾叶对照药材同法制备对照药材溶液。吸取供试品溶液和对照溶液各2μL分别点于同一硅胶G薄层板和反向薄层色谱硅胶预制板,于日光下及紫外光灯(365 nm)下检视。采用GC-MS测定艾绒挥发油类成分比较正品艾绒与艾绒混伪品的气相色谱图差异。结果:硅胶薄层色谱及C_(18)反相薄层色谱均可在日光、紫外光灯(365 nm)下出现特异性斑点。气相色谱图显示混伪品艾绒在挥发油类成分含量上存在差异,且检出了正品艾绒中没有检出的成分(十五烷、菊薁)。结论:采用硅胶薄层色谱、C_(18)反相薄层色谱2种方法能较快、较准确地鉴别艾绒混伪品,结果稳定。GC-MS能够检测出混伪品艾绒的组分差异。

Objective:Thin layer chromatography(TLC)and gas chromatography-mass spectrometry(GC-MS)were used to identify moxa floss adulterant.Methods:The authentic moxa floss and adulterant were heated under reflux with petroleum ether(60~90℃),evaporated to dryness,and then dissolved in cyclohexane to yield the test solution.The reference Folium Artemisiae Argyi was used to prepare the reference solution with the same method.A total of 2μL of test solution and 2μL of reference solution were respectively dripped on the same Merck TLC silica gel plate and reversed-phase TLC silica gel precoated plate and observed under sunlight and ultraviolet light(365 nm).GC-MS was used to determine the volatile oil constituents of moxa floss and gas chromatograms of the authentic product and the adulterant were compared.Results:Silica gel TLC plate and C_(18)reversed-phase TLC plate showed specific spots under sunlight and ultraviolet light(365 nm).According to the gas chromatograms,the content of volatile oil constituents was different between the authentic moxa floss and the adulterant and pentadecane and chamazulen which were found in the adulterant failed to be detected in authentic moxa floss.Conclusion:Silica gel TLC and C_(18)reversed-phase TLC can quickly and accurately distinguish moxa floss adulterant,with stable result.GC-MS can be used to detect the differential components in the adulterant.