AQC柱前衍生/UPLC-MS/MS测定蜂蜜中的内源性氨基酸和牛磺酸成分

Determination of Endogenous Amino Acids and Taurine in Honey by Ultra-performance Liquid Chromatography-Tandem Mass Spectrometry with AQC Pre-column Derivation

基于6-氨基喹啉基-N-羟基-琥珀酰亚氨基甲酸酯(AQC)柱前衍生,建立了蜂蜜中23种内源性氨基酸和牛磺酸成分的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法。样品经水提取,AQC衍生后,采用AccQ-Tag Ultra C_(18)(2.1 mm×100 mm,1.7μm)色谱柱分离,以乙腈-10 mmol/L甲酸铵溶液为流动相进行梯度洗脱,电喷雾电离,正离子多反应监测模式检测,内标法定量。结果表明:24种目标物在各自浓度范围内线性关系良好,相关系数(r)均不小于0.993 0;检出限为0.03~0.15μmol/L,定量下限为0.1~0.5μmol/L;低、中、高3个加标水平下的回收率为90.5%~109%,相对标准偏差为1.2%~4.7%。通过对39批次真蜂蜜、39批次掺假蜂蜜、10批次糖浆进行检测,发现不同蜜源蜂蜜中目标物的种类与含量差异较大,掺假蜂蜜中氨基酸与牛磺酸的含量明显低于真蜂蜜,糖浆中未检出目标物。该方法快速、简便、准确、灵敏,适用于蜂蜜中氨基酸和牛磺酸的快速定性、定量分析,可为蜂蜜的质量评价和掺假鉴别提供技术支持。

An ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate(AQC)pre-column derivation was established for the determination of 23 endogenous amino acids and taurine in honey.The honey samples were extracted with water and derived with AQC,then separated on an AccQ-Tag Ultra C_(18)column(2.1 mm × 100 mm,1.7 μm)by gradient elution with acetonitrile-10 mmol/L ammonium formate as the mobile phase,and finally analyzed by mass spectrometry in positive ion multiple reaction monitoring mode and quantified by internal standard method.The calibration curves for amino acids and taurine showed good linearity in their respective concentration ranges, with correlation coefficients(r)not less than 0.993 0.The limits of detection(LODs)and the limits of quantitation(LOQs)were in the range of 0.03-0.15 μmol/L and 0.1-0.5 μmol/L, respectively.The average recoveries ranged from 90.5%to 109%,with relative standard deviations of 1.2%-4.7%.Through analyses on 39 batches of real honey,39 batches of adulterated honey and 10 batches of syrup,it was found that the types and content of target compounds in different honey sources differed largely.The contents of amino acids and taurine in adulterated honey were significantly lower than that in real honey,and no target compounds were detected in syrup.This method was simple,sensitive and accurate,and it could be used for the determination of free amino acids and taurine in honey,providing a technical support for the quality evaluation and authenticity identification.