高效液相色谱-电感耦合等离子体质谱联用法测定东海乌参样品中的二价汞、甲基汞、乙基汞和苯基汞

目的建立高效液相色谱-电感耦合等离子体质谱法(high performance liquid chromatography-inductively coupled plasma-mass spectrometry,HPLC-ICP-MS)测定东海乌参样品中的二价汞、甲基汞、乙基汞和苯基汞4种汞形态的含量。方法样品经25%KOH微波萃取1 h,采用Agilent Zorbax Plus C_(18)色谱柱分离,以10 mmol/L醋酸铵+0.12%L-半胱氨酸缓冲盐及2%甲醇作为流动相进行梯度洗脱,采用ICP-MS进行检测。结果二价汞、甲基汞、乙基汞和苯基汞在10 min内完成分离,检出限分别为0.8、0.2、0.2和0.8 ng/m L;在0.10、0.20和0.40mg/kg 3个加标水平下,4种汞化合物的回收率为78.1%~105.8%,相对标准偏差为5.3%~8.2%。结论本方法简便、快速、准确,可适用于汞形态的分析。

Determination of bivalent mercury, methyl-mercury, ethyl-mercury and phenyl-mercury in Acaudina leucoprocta by high performance liquid chromatography-inductively coupled plasma-mass spectrometry

Objective To establish a method for determination of 4 kinds of mercury speciation including bivalent mercury, methl-mercury, ethyl-mercury and phenyl-mercury in Acaudina leucoprocta by high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). Method After microwave extraction with 25% potassium hydroxide (KOH) for 1 h, the sample was separated by Agilent Zorbax Plus C18 column with the mobile phase of 10 mmol/L ammonium acetate/0.12% L-cysteine/methanol for gradient elution and then detected by ICP-MS. Results Bivalent mercury, methl-mercury, ethyl-mercury and phenyl-mercury could be separated within 10 min. The detect limits were 0.8, 0.2, 0.2 and 0.8 ng/mL, respectively. The recoveries of 4 kinds of mercury speciation spiked at 3 levels of 0.10, 0.20 and 0.40 mg/kg were ranged from 78.1% to 105.8% with the relative standard deviations of 5.3%~8.2%. Conclusion The developed method is simple, rapid and accurate, which can be used for determination of mercury speciation.