采用超高效液相色谱-串联质谱法同时测定香精、香料中的3种甜味剂和5种色素。样品经氨水-甲醇混合溶液提取后,采用Waters BEH C18色谱柱分离,以不同比例的10 mmol·L-1乙酸铵溶液(此溶液每升含冰乙酸1 mL)和甲醇的混合液为流动相进行梯度洗脱。对甜味剂采用电喷雾负离子模式,对色素采用电喷雾正离子模式,采用多反应监测模式进行测定。8种待测物质的质量浓度在一定范围内与峰面积呈线性关系,检出限(3S/N)在0.09~1.2 mg·kg-1之间。加标回收率在82.9%~118%之间,测定值的相对标准偏差(n=5)均小于6%。

UHPLC-MS/MS was applied to the determination of 3 sweeteners and 5 pigments in samples of essence or spice. The sample was extracted with a mixture of methanol and ammonia. The extract was separated on Waters BEH C18 column, with a mixture of methanol and 10 mmol·L-1 ammonium acetate solution (containing 1 mL of glacial acetic acid per liter of solution) in various ratios as mobile phase in gradient elution. ESI+ (for pigment sample), ESI- (for sweetener sample) and MRM were adopted in MS. Linear relationships were found between values of peak areas and mass concentrations of the 8 analytes in definite ranges, with detection limits (3S/N) in the range of 0.09-1.2 mg·kg-1. Results of test for recovery found by standard addition method were in the range of 82.9%-118%, and RSD′s (n=5) were less than 6%.