高效液相色谱-串联质谱法测定液体乳中氯酸盐和高氯酸盐

Determination of chlorate and perchlorate in liquid milk by high performance liquid chromatography-tandem mass spectrometry

目的建立高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)测定液体乳中的氯酸盐和高氯酸盐的分析方法。方法样品经0.2%甲酸水-甲醇(10:90,V:V)提取,HLB固相萃取柱净化。经Acclaim Trinity P1复合阴离子交换柱(100 mm×2.1 mm,3μm)洗脱。在流速0.5 m L/min下以乙腈-20 mmo L/L甲酸铵溶液(70:30,V:V)作为流动相,梯度分离。采用三重四极杆电喷雾离子源电离-多反应监测(multiple reaction monitoring,MRM)-负离子监测模式检测,分别以氯酸根-^(18)O_(3)高氯酸根-^(18)O_(4)为内标物,进行内标法定量。结果氯酸盐和高氯酸盐分别在0.0~50.0μg/kg和0.0~25.0μg/kg范围内线性关系良好,相关系数r^(2)都大于0.999。方法的测定低限分别为0.4μg/kg和0.6μg/kg。回收率为80.0%~93.6%,相对标准偏差(relative standard deviation,RSD)为2.14%~6.68%,结论该方法提取率高,准确可靠,适用于液体乳中氯酸盐和高氯酸盐的定量分析。

Objective To establish a method for the determination of chlorate and perchlorate in liquid emulsion by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS). Methods The samples were extracted by 0.2% formate water and methanol(10:90, V:V) and purified by HLB solid phase extraction column. The Acclaim Trinity P1 composite anion exchange column(100 mm×2.1 mm, 3 μm) was used for elution. Acetonitrile-20 mmol/L ammonium formate(70:30, V:V) was used as the mobile phase at the flow rate of 0.5 mL/min for gradient separation. Triple quadrupole electrospray ion source(ESI source) ionization-multiple reaction monitoring(MRM)-anion monitoring mode was used for detection. Using-^(18)O_(3) and-^(18)O_(4) as internal standards, internal standard method was used for quantitative analysis. Results The linear relationships of chlorate and perchlorate were good in the ranges of 0.0-50.0 g/kg and 0.0-25.0 g/kg, respectively, and the correlation coefficients r2 were greater than 0.999. The lower limits of the method were 0.4 μg/kg and 0.6 μg/kg, respectively. The recovery rates were 80.0%-93.6%, and relative standard deviations(RSDs) were 2.14%-6.68%. Conclusion The experimental results showed that the method had a high extraction rate, was accurate and reliable, and was suitable for the quantitative analysis of chlorate and perchlorate in liquid milk.