超高效液相色谱串联质谱法同时测定面粉中曲酸和噻二唑

Determination of Kojic Acid and 2-mercapto-5-methyl-1,3,4-thiadiazde in Flour by Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry/Mass Spectrometry

建立超高效液相色谱-串联四级杆质谱法(UPLC-MS/MS)同时测定面粉中曲酸和噻二唑的方法。色谱柱为ACQUITY UPLC®BEH C18(2.1 mm×100 mm,1.7μm),流动相为0.1%甲酸5 mmol·L^-1甲酸铵水溶液∶乙腈,梯度洗脱,流速为0.45 mL·min^-1。采用多反应监测模式(multiple reaction monitoring,MRM),曲酸为ESI正电离源,定量离子对140.3/69;噻二唑为ESI负电离源,定量离子对130.8/57.9。样品经纯水超声提取30 min,过膜后直接测定,外标法定量。结果表明,曲酸在1.00~50.00μg·L-1,噻二唑在10.00~500.00μg·L^-1范围内线性关系良好,相关系数≥0.995。面粉样品中3个浓度加标水平即曲酸含量0.10、0.20和0.40 mg·kg^-1,回收率为100.00%~105.00%,相对标准偏差为2.50%~10.72%;噻二唑含量1.00、2.00和4.00 mg·kg^-1,回收率为86.00%~89.00%,相对标准偏差为3.65%~9.97%。该方法操作简便、回收率高,可用于大批量面粉中曲酸和噻二唑的同时测定。

A new method was developed for the determination of Kojic acid(KA)and 2-mercapto-5-methyl-1,3,4-thiadiazde(MMTD)in flour by ultra high performance liquid chromatography-tandem mass spectrometry/mass spectrometry.The chromatography column was ACQUITY UPLC®BEH C18(2.1 mm×100 mm,1.7μm),mobile phases were 0.1%formic with 5 mmol·L-1 ammonium formate in water solution and acetonitrile,with gradient elution,the flow rate was 0.45 mL·min-1.Using multiple reaction monitoring(MRM)mode,the ESI mass spectrometry was positive ion source for KA,143.1/69 and negative ion source for MMTD,130.8/57.9.The sample was extracted by water solution,the quantitation was carried out with the external standard method.The linear range of the method was 1.00~50.00μg·L-1 for KA and 10.00~500.00μg·L-1 for MMTD,with a correlation coefficient not less than 0.995.The recoveries in flour matrix at the three spiked levels of 0.10,0.20,0.40 mg·kg^-1 for KA and 1.00,2.00,4.00 mg·kg^-1 for MMTD,were in the range of 100.00%~105.00%for KA and 86.00%~89.00%for MMTD,and the relative standard deviations were in the range of 2.50%~10.72%for KA and 3.65%~9.97%for MMTD.The method is simple,high recoveries and is suitable for the simultaneous confirmation and quantificaition of KA and MMTD residue in flour which applies in batch detection.