氩气在线稀释-电感耦合等离子体质谱法直接测定饱和食盐水中总砷

Determination of Total Arsenic in Salt Saturated Water by Inductively Coupled Plasma Mass Spectrometry with Online Dilution with Argon

应用氩气在线稀释克服了电感耦合等离子体质谱法直接测定饱和食盐水中总砷时高盐的基体效应。运用碰撞池技术,有效消除40 Ar35Cl+对砷的干扰;通过在线加入甲醇溶液,提高砷的灵敏度。试验结果表明:砷的线性范围在10.0μg·L^(-1)以内,检出限(3s)为0.092μg·L^(-1),加标回收率在90.2%~111%之间,测定值的相对标准偏差(n=6)在1.7%~4.2%之间。

Online dilution with argon was applied to direct determination of total arsenic in salt saturated water by inductively coupled plasma mass spectrometry to overcome matrix effect of high salt containing sample.The interference of 40 Ar35 Cl＋to arsenic was reduced by using collision cell technique.Sensitivity of arsenic was raised by adding methanol solution.As shown by the results,the linearity range of arsenic was within 10.0μg·L^（-1）,with detection limit（3 s）of 0.092μg·L^（-1）.Values of recovery obtained by standard addition method were in the range of 90.2%-111%,and RSDs（n=6）were in the range of 1.7%-4.2%.