Chemistry Department, Federal University of Minas Gerais, Belo Horizonte, Av. Antônio Carlos n° 6627, CEP 31270-901, Belo Horizonte-MG, Brazil.
J Anal Toxicol. 2011 Oct;35(8):571-6. doi: 10.1093/anatox/35.8.571.
A method for direct determination of manganese (Mn) in human serum by graphite furnace atomic absorption spectrometry (GFAAS) was proposed in this work. The samples were only diluted 1:4 with nitric acid 1% (v/v) and Triton(®) X-100 0.1% (v/v). The optimization of the instrumental conditions was made using multivariate approach. A factorial design (2(3)) was employed to investigate the tendency of the most intense absorbance signal. The pyrolysis and atomization temperatures and the use of modifier were available and only the parameter modifier use did not have a significant effect on the response. A Center Composed Design (CCD) presented best temperatures of 430 °C and 2568 °C for pyrolysis and atomization, respectively. The method allowed the determination of manganese with a curve varying from 0.7 to 3.3 μg/L. Recovery studies in three concentration levels (n=7 for each level) presented results from 98 ± 5 to 102 ± 7 %. The detection limit was 0.2 μg/L, the quantifying limit was 0.7 μg/L, and the characteristic mass, 1.3 ± 0.2 pg. Intra- and interassay studies showed coefficients of variation of 4.7-7.0% (n=21) and 6-8%(n=63), respectively. The method was applied for the determination of manganese in 53 samples obtaining concentrations from 3.9 to 13.7 μg/L.
本工作提出了一种用石墨炉原子吸收光谱法（GFAAS）直接测定人血清中锰（Mn）的方法。样品仅用 1%（v/v）硝酸和 0.1%（v/v）Triton(®) X-100 稀释 1:4。通过多元方法优化仪器条件。采用析因设计（2(3)）研究了最强烈吸收信号的趋势。热解和原子化温度以及使用改性剂是可用的，只有改性剂使用参数对响应没有显著影响。中心组合设计（CCD）给出了最佳的热解和原子化温度分别为 430°C 和 2568°C。该方法允许在 0.7 至 3.3 μg/L 的范围内测定锰。在三个浓度水平（每个水平 7 个重复）进行的回收研究结果表明回收率为 98 ± 5%至 102 ± 7%。检测限为 0.2 μg/L，定量限为 0.7 μg/L，特征质量为 1.3 ± 0.2 pg。日内和日间研究的变异系数分别为 4.7-7.0%（n=21）和 6-8%（n=63）。该方法应用于 53 个样品中锰的测定，得到的浓度范围为 3.9 至 13.7 μg/L。
