液相色谱-原子荧光光谱法检测海产品中4种形态砷含量的方法研究

Method study for determination of four arsenic species in seafood by liquid chromatography-atomic fluorescence spectrometry

目的探索并建立海产品中4种形态砷含量的液相色谱-原子荧光光谱检测方法。方法粉碎均匀的样品用浓度为0.15 mol/L硝酸溶液在90℃的恒温烘箱中热浸提2.5 h,提取完毕后用离心机将样液离心分离,分离好的上清液再用正己烷提取,弃去上层正己烷清液,共提取2次,被提取的样液合并后先过C_(18)小柱,再过0.45μm滤膜后,经过形态分析仪预处理,由高效液相色谱仪分离,最后用原子荧光光度计检测。结果测定了0μg/L~100μg/L范围内4种形态砷的混合标准曲线,4种形态线性方程的相关系数均>0.9990,方法的检出限均为0.50μg/L,方法的加标回收率:三价砷为88.0%~90.0%、五价砷为90.0%~100.0%、一甲基砷为90.0%~91.0%、二甲基砷为90.0%~91.0%,方法的精密度:三价砷为4.00%~9.75%、五价砷为4.68%~5.16%、一甲基砷为3.78%~8.07%、二甲基砷为4.17%~6.96%。结论用该法测定海产品中4种形态砷含量,方法的精密度和准确度及线性关系均比较满意,适合用于海产品中形态砷含量的检测。

Objective To establish a method for the determination of four arsenic species in seafood by high performance liquid chromatography-atomic fluorescence spectrometry(HPLC-AFS). Methods The samples were extracted with 0. 15 mol/L nitric acid solution at 90 ℃ for 2. 5 hours. After extraction,the samples were centrifuged and separated. The supernatant was extracted twice with n-hexane. The n-hexane was discarded,and the purified solution was pretreated by a morphometric analyzer after passing through the C_(18) column and filter membranes of 0. 45 μm. The purified solution was separated by high performance liquid chromatography and detected by atomic fluorescence photometer. Results The results showed that good linear range of the four arsenic species from 0 to 100 μg/L were obtained. The correlation coefficient of four arsenic species were greater than 0. 999 0,and the detection limits were all 0. 50 μg/L. The standard recovery rates of the method were 88. 0%-90. 0% for trivalent arsenie [As(Ⅲ) ],90. 0%-100. 0% for pentavalent arsenie [As(Ⅴ) ],90. 0%-91. 0% for monomethylarsine(MMA) and 90. 0%-91. 0% for dimethylarsine(DMA). The precisions of the method were 4. 00%-9. 76% for As(Ⅲ),4. 73%-5. 16% for As(Ⅴ),3. 74%-8. 07% for MMA and 4. 17%-6. 99% for DMA. Conclusion The precision,accuracy and linear relationship of this method are satisfactory,and it is suitable for the determination of arsenic species in seafood.