Tallinn University of Technology, Department of Chemistry, Akadeemia tee 15, Tallinn, Estonia.
J Chromatogr A. 2011 Aug 5;1218(31):5298-304. doi: 10.1016/j.chroma.2011.06.016. Epub 2011 Jun 17.
In this study, we introduced a simple and sensitive method of capillary electrophoresis with ultraviolet light-emitting diode-induced native fluorescence (UV-LEDIF) detection for the determination of isoquinoline alkaloids in extracts of Chelidonium majus L. Samples were extracted with acidic methanol and the extracts were directly analysed by CE. Simultaneous determination of protopine, chelidonine, coptisine, sanguinarine, allocryptopine, chelerythrine and stylopine was performed in 20mM phosphate buffer (pH 3.1). The baseline separation of these alkaloids was finished within 20 min. As these alkaloids have native fluorescence, they were directly detected using the commercially available UV light emitting diode without troublesome fluorescent derivatisation. Satisfactory LOD values were obtained for the studied compounds considering their appearance in natural extracts. Lower limits of detection were 0.05 μg/mL for protopine, 0.06 μg/mL for stylopine and allocryptopine, 0.07 μg/mL for chelidonine, 0.22 μg/mL for sanguinarine, 1.7 μg/mL for chelerythrine and 5.5 μg/mL for coptisine. The developed method was successfully applied to determine the contents of seven alkaloids in the aerial parts of Chelidonium majus L, which varied from 0.025 to 0.763% (w/w). Also, to demonstrate the potential of the proposed CE method, an estimation of the cytotoxic properties of selected Celandine alkaloids in a natural extract was carried out.
在这项研究中，我们引入了一种简单灵敏的毛细管电泳-紫外发光二极管诱导 native fluorescence（UV-LEDIF）检测方法，用于测定Chelidonium majus L.提取物中的异喹啉生物碱。样品用酸性甲醇提取，提取物直接用 CE 分析。在 20mM 磷酸盐缓冲液（pH 3.1）中同时测定原阿片碱、白屈菜碱、黄连碱、血根碱、阿柯若因、白屈菜红碱和石杉碱甲。这些生物碱具有 native fluorescence，因此可以直接使用市售的紫外发光二极管进行检测，无需繁琐的荧光衍生化。考虑到这些化合物在天然提取物中的存在，该方法对所研究的化合物具有令人满意的检出限。对于原阿片碱、石杉碱甲和阿柯若因的检出限为 0.05μg/mL，白屈菜碱为 0.06μg/mL，血根碱为 0.22μg/mL，白屈菜红碱为 1.7μg/mL，黄连碱为 0.7μg/mL。所建立的方法成功地应用于测定 Chelidonium majus L.地上部分七种生物碱的含量，范围为 0.025%至 0.763%（w/w）。此外，为了展示所提出的 CE 方法的潜力，对天然提取物中选定的白屈菜生物碱的细胞毒性进行了估计。
