超高效合相色谱-串联质谱法快速测定枸杞中甜菜碱含量（英文）

枸杞作为传统的中药材,具有滋补肝肾、益精明目的功效,亦可作为功能性食品被广泛食用。基于超高效合相色谱-质谱(UPC~2-MS),建立了一种快速、灵敏地定量测定枸杞中甜菜碱(指标化合物)含量的新方法。采用ACQUITY UPC2BEH 2-EP色谱柱(150 mm×2.1 mm,1.7μm),以0.7 mL/min超临界CO_2-甲醇(80∶20,v/v)等度洗脱,成功分离了枸杞中的甜菜碱。在该分离过程中,0.1%(v/v)甲酸作为改性剂;背压为1.31×10~7Pa;柱温为40℃;进样体积为1μL;保留时间为3 min。质谱检测工作于电喷雾(ESI)正离子模式和选择离子监测(SIR)模式。在上述条件下得到线性回归方程。其相关系数为0.999 2,检测范围为0.5～50.0μg/mL,检出限为0.013μg/mL。随后,通过对精度、重复性、稳定性和加标回收率(平均值96.3%)的分析,验证了该方法的有效性。最后,将所建立的方法应用于11批样品的分析。结果表明,该方法可较好地用于枸杞的质量控制与分析评价。

Fast determination of betaine in Lycii Fructus by ultra-performance convergence chromatography-tandem mass spectrometry

Over the past 2500 years, Lycii Fructus has been widely used as a functional food and tonic in Chinese herbal medicine. It can nourish the liver and kidneys, moisten the lungs, and improve eyesight. In this study, a new rapid and sensitive method has been developed for the quantitative determination of betaine (index compound) in Lycii Fructus by using ultra-performance convergence chromatography-tandem mass spectrometry (UPC²-MS). The separation of betaine was successfully achieved on an ACQUITY UPC² BEH 2-EP column (150 mm×2.1 mm, 1.7 μm), with isocratic elution by a CO₂-methanol (80:20, v/v) solvent at a flow rate of 0.7 mL/min. The conditions used in the separation process were as follows:modifier, 0.1% (v/v) formic acid in methanol; column temperature, 40℃; backpressure, 1.31×10⁷ Pa; injection volume, 1 μL; and retention time, 3 min. The MS system was equipped with an electrospray ionization (ESI) ion source and operated in the selected ion recording (SIR) and positive ion mode. Under the abovementioned conditions, the calibration curve was obtained. The linear range of detection was 0.5-50.0 μg/mL, with a correlation coefficient of 0.9992, and the limit of detection (LOD) was found to be 0.013 μg/mL. The validity of the method was tested by analyses of precision, repeatability, stability, and accuracy (average recovery:96.3%). Finally, the developed method was applied to analyze 11 batches of samples. The results indicated that this method was suitable for evaluating the quality of Lycii Fructus.