中文摘要：

以巯基修饰磁性纳米材料 Fe3O4@SiO2-SH 为固相萃取吸附剂从花蛤样品中富集痕量的甲基汞,2．0 mol/L HCl溶液为洗脱液,KBrO3和KBr的混合溶液为消解液,用原子荧光分光光度计测定.研究了影响甲基汞富集和测定的因素,包括溶液的pH值、吸附剂的用量、吸附时间等.利用标准曲线法定量.工作曲线在1．0~40ng/L的范围内线性关系良好,相关系数为 r=0．9997,相对标准偏差为1．6%（n =11）,检出限为0．2 ng/L,回收率为95%~100%,显示了较高的灵敏度和精密度.

英文摘要：

Fe3 O4@SiO2-SH magnetic nanomaterials was applied as solid phase extraction sorbent for enrich-ment of trace methylmercury from Ruditapes philippinarum samples. HCl solution （2. 0mol/L） was used as eluent,and a mixture of KBrO3 and KBr as digestion solution. The concentration of Hg2＋ in digestion solution was determined with an atomic fluorescence spectrophotometer. To study the factors that affected the enrichment and determination of methylmercury,the conditions including solution pH,amount of sorbent,and equilibrium time were optimized. The standard curve in the range of 1. 0 -40. 0 ng/L showed good linearity with correlation coefficient over 0 . 999 . The recoveries of spiked sample ranged from 95% to 100%. Relative standard deviation was 1. 6% after 11 times of repeat measurement,and the detection limit was 0. 2 ng/L. This method for methylmercury determination in Ruditapes philippinarum samples exhibited high sensitivity and pre-cision.