高效液相色谱-串联四极杆质谱法测定荔枝中降糖氨酸A和亚甲基环丙基甘氨酸

Determination of hypoglycine A and methylenecyclopropylglycine in litchi fruit by high performance liquid chromatography-tandem quadrupole mass spectrometry

建立高效液相色谱-串联四极杆质谱定量分析荔枝中降糖氨酸A和亚甲基环丙基甘氨酸两种降糖氨酸的测定方法。荔枝样品以90%乙醇为提取溶剂进行超声提取,离心取上清,氮吹后用水复溶。经丹磺酰氯衍生化后,采用Waters HSS T3色谱柱(100 mm×2.1 mm,1.8μm)进行分离,柱温为35℃,水(含0.1%甲酸)和乙腈为流动相,梯度洗脱,流量为0.3 mL/min。质谱采用电喷雾电离源,正离子扫描,多反应监测模式进行检测。两种降糖氨酸的质量浓度在0.01~0.50μg/mL范围内与其色谱峰面积线性良好,相关系数均大于0.999,降糖氨酸A的检出限为0.05 mg/kg,亚甲基环丙基甘氨酸的检出限为0.08 mg/kg,加标回收率为81.4%~98.7%,相对标准偏差为3.2%~5.9%(n=6)。该方法操作简单,分析时间短,灵敏度高,准确可靠,为荔枝中降糖氨酸A和亚甲基环丙基甘氨酸两种降糖氨酸的测定提供了有效的技术手段。

A high performance liquid chromatography-tandem mass spectrometry method was established for the determination of hypoglycine A and methylenecyclopropylglycine in litchi fruit.The litchi fruit samples were extracted by ultrasonic with 90%ethanol and the supernatant was centrifuged,after nitrogen blowing,the samples were redissolved with water.With dansyl chloride derivatization,the samples were separated on a Waters HSS T3 column(100 mm×2.1 mm,1.8μm)with the column temperature at 35℃.Water containing 0.1%formic acid and acetonitrile were used as mobile phase by gradient elution at the flow rate of 0.3 mL/min.The analytes were detected by electrospray ionization source,positive ion scanning and multi reaction monitoring mode.The mass concentration of the two hypoglycemic amino acids had good linearity with their chromatographic peak areas in the range of 0.01-0.50μg/mL,and the correlation coefficients were greater than 0.999.,the detection limit of hypoglycine A was 0.05 mg/kg,the detection limit of methylenecyclopropylglycine was 0.08 mg/kg,the average recoveries of two analytes were from 81.4%to 98.7%,and the relative standard deviations were from 3.2%to 5.9%(n=6).The method has the advantages of simple operation,short analysis time,high sensitivity,accuracy and reliability,and provides an effective way for the determination of hypoglycine A and methylenecyclopropylglycine in litchi.