纳米TiO_2富集分离石墨炉原子吸收法测定食品中的镉

Determination of Cd in Food Sample by Nanometer-Titanium Dioxide Preconcentration and Separation-Furnace Atomic Absorption Spectroscopy

以石墨炉原子吸收为检测手段,研究纳米TiO2对金属Cd的吸附性能,考察吸附和洗脱的主要影响因素。结果表明:在pH8～10范围内,纳米TiO2对金属Cd具有良好的吸附性,吸附率达到95.0%,3mol/L的硝酸即可将纳米TiO2吸附的Cd完全洗脱。在优化的试验条件下,静态吸附量为15.9mg/g。本法的检出限为(3σ)2.02×10-13g,RSD为3.18%～5.21%,富集倍数为75倍,加标回收率在98.5%～100.4%之间。

Detected by Furnace Atomic Absorption Spectroscopy.The adsorption and desorption behavior of nanometer TiO2 towards Cd was investigated.It was found that the adsorption fraction of Cd was 95.0 % at pH 810 and the elution with 3 mol/L HNO3 was sufficient for Cd.The adsorption capacities was 15.9 mg/g.The detection limit （3σ） was 2.02×10^-13 g,and RSD was 3.18 %-5.21 %.The enrichment multiple was 75,The recoveies were 98.5 %-100.4 %.