固相萃取-超快速液相色谱-串联质谱法同时测定血液中的4种苏丹染料

建立了血液样品中4种苏丹染料（苏丹Ⅰ、Ⅱ、Ⅲ和Ⅳ）的固相萃取-超快速液相色谱-串联质谱（UFLC-MS/MS）测定方法。样品经乙腈涡旋振荡提取，上清液加等体积水稀释混匀后移入C18固相萃取小柱净化，采用Agilent Eclipse Plus C18色谱柱（100 mm×2.1 mm，1.8 μm）以0.1%（v/v）甲酸水溶液和0.1%（v/v）甲酸乙腈溶液为流动相梯度洗脱分离，电喷雾电离（ESI）正离子多反应监测模式进行定量分析。讨论了苏丹Ⅲ和苏丹Ⅳ的偶氮基团E-Z光学异构现象，并对影响因素进行了分析。结果4种苏丹染料在0.1~20.0 μg/L范围内线性关系良好，相关系数均大于0.999；在低、中、高3个加标水平的平均回收率为93.0%~108.2%，相对标准偏差为4.8%~9.5%；方法的检出限（LOD）为0.06 μg/L，定量限（LOQ）为0.2 μg/L。本方法准确、快速、灵敏，可用于血液样品中苏丹类染料的检测分析。

Simultaneous determination of four Sudan dyes in blood by solid-phase extraction combined with ultra-fast liquid chromatography-tandem mass spectrometry

A method for the simultaneous determination of Sudan Ⅰ, Ⅱ, Ⅲ, and Ⅳ in blood samples by solid-phase extraction (SPE) combined with ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) has been established. The samples were extracted with acetonitrile by vortex and vibrate technique, and then the supernatant was diluted with equal volume of water and cleaned up by a C18 SPE column. The separation was performed on an Agilent Eclipse Plus C18 column (100 mm×2.1 mm, 1.8 μm) by gradient elution with acetonitrile containing 0.1% (v/v) formic acid and 0.1% (v/v) formic acid aqueous solution as the mobile phases. The electrospray ionization (ESI) source in the positive mode and multiple reaction monitoring (MRM) mode were used for the quantitative analysis. In addition, the phenomenon of E-Z optical isomer occurred by the azo group from Sudan Ⅲ and Ⅳ was found, and the influencing factors were discussed. The results showed that the calibration curves were in good linearity for the four Sudan dyes ranged from 0.1 to 20.0 μg/L with the correlation coefficients of more than 0.999. The average recoveries were from 93.0% to 108.2% with the relative standard deviations (RSDs) from 4.8% to 9.5%. The limits of detection (LODs) and the limits of quantification (LOQs) were 0.06 μg/L and 0.2 μg/L for the four analytes, respectively. The developed method is simple, rapid, and highly sensitive. It can be used for the determination of trace Sudan dyes in blood samples.