响应面法优化石墨炉原子吸收光谱法直接测定小鼠全血铅

目的]探讨响应面法优化石墨炉原子吸收光谱法直接测定全血中铅。方法]以0．5％Triton X-100溶液做血液稀释剂，0．05％氧化钯＋0．1％硝酸混合溶液为基体改进剂，直接进样测定。在单因素的基础上，采用中心组合设计和响应面分析法优化灰化温度、原子化温度和基体改进剂用量等因素，并在优化条件下测定小鼠全血铅结果。结果]响应面法优化石墨炉原子吸收谱法直接测定小鼠全血铅的最优测定条件为灰化温度760．85％，原子化温度2486．80％，基体改进剂加入量0．97mL。在已优化的条件下测定铅的检出限为0．204μg／L，相对标准差（n=6）为1．76％。染毒小鼠的全血铅含量为82．1μg/L，加标回收率为96．5％-98．4％。结论]响应面法优化石墨炉原子吸收光谱法不需消化和离心，直接进样，简便快速和准确，适用于染毒小鼠全血铅的测定。

Direct Determination of Lead in Mouse Blood by Graphite Furnace Atomic Absorption Spectrometry Optimized by Response Surface Methodology

Objective ] To explore a method for direct determination of lead in mouse blood by graphite furnace atomic absorption spectrometry （GFAAS） with optimization using response surface methodology. Methods ] After blood samples were diluted with 0.5% Triton X-100 solution, lead in blood was directly determined by GFAAS using a mixture solution of 0.05% PdCl2 and 0.1% HNO3 as modifier. The effects of matrix modifier dosage, ashing temperature, and atomization temperature on absorbance were examined by central composite design and response surface methodology. Results ] The optimum extraction conditions were as follows： ashing temperature, 760.85℃ ; atomization temperature, 2486.80℃ ; and dosage of matrix modifier, 0.97 mL. Under the optimal conditions, the value of detection limit for Pb was 0.204 μg/L, and the relative standard deviation （RSD） for six replicate determinations of Pb was 1.76%. Lead in blood of mice was successfully detected at a concentration of 82.1 μg/L, and the recoveries were 96.5%-98.4%. Conclusion ] The method is simple, rapid, and accurate by direct injection without digestion or centrifugation, which can be applied to lead determination in mouse blood.