液相色谱-离子阱-飞行时间质谱法测定调味品中9种酸性工业染料

摘要

A liquid chromatography-ion trap-time of flight mass spectrometric (LCMS-IT-TOF)method for the determination of 9 acidic dyes in soy sauce and spice condiments such as chilli sauce,dried pimiento and chinese prickly ash was established.The samples were extracted with methanol-water(80 ∶ 20)solution and cleaned on a weak anion exchange solid phase extraction column (Oasis WAX).The separation of target compounds was carried out on a Shimadu Shim-pack XR-ODS (2.0 mm × 100 ram,2.2 μm) column using 10 mmol · L-1 ammonium acetate-methanol as mobile phase by gradient elution at a flow rate of 0.2 mL · min-1.The identification of the analytes was achieved in negative ion mode with electrospray ionization source and the quantification was carried out by the external standard method.The results showed that the matrix-matched calibrations of 9 acid dyes had good linear relationships in the certain concentration ranges with their correlation coefficients (r2) more than 0.99.Average recoveries of the acidic dyes at three spiked levels ranged from 64.8％ to 106.0％ with relative standard deviations (RSD,n =5) no more than 6.7％.The proposed method was simple,rapid and highly sensitive.According to the multi-stage mass spectrometry data,the accuracy of qualitative analysis by the method was improved.The method was suitable for the simultaneous determination of acidic dyes residues in soy sauce and spice condiments.%建立了辣椒酱、干辣椒、花椒等酱类和香辛料类调味品中9种酸性工业染料的液相色谱-离子阱-飞行时间质谱(LCMS-IT-TOF)检测方法.样品用甲醇-水(80∶20)溶液提取,经弱阴离子交换(Waters Oasis WAX)固相萃取柱净化,以Shimadu Shim-pack XR-ODS(2.0 mm×100 mm,2.2 μm)柱进行分离,采用10 mmol/L乙酸铵溶液-甲醇为流动相梯度洗脱,流速为0.2 mL/min.采用电喷雾离子化源,在负离子模式下进行检测,外标法定量.结果表明,9种酸性工业染料的基质校准曲线在一定范围内线性关系良好,相关系数均大于0.99.3个加标水平的平均回收率为64.8％～ 106.0％,相对标准偏差(n=5)不高于6.7％.该方法操作简单、灵敏度高、分析时间短,离子阱飞行时间多级质谱的定性功能增加了定性结果的可靠性,适用于酱类和香辛料类调味品中9种酸性工业染料的同时测定.