Department of Analytical Chemistry, Faculty of Science, Palacký University in Olomouc, 17. listopadu 12, 771 46, Olomouc, Czech Republic.
Department of Orthopedics, Faculty of Medicine and Dentistry, Palacký University Olomouc, University Hospital Olomouc, I. P. Pavlova 6, 775 20, Olomouc, Czech Republic.
Talanta. 2020 Oct 1;218:121150. doi: 10.1016/j.talanta.2020.121150. Epub 2020 May 13.
The presented work proposes a novel analytical ICP-MS-based approach for the accurate and precise chromium speciation in biological tissues. The determination of total Cr(VI) and soluble Cr(III) species was carried out by alkaline EDTA extraction followed by their separation using ion-exchange high-performance liquid chromatography inductively coupled plasma mass spectrometry (IE-HPLC-ICP-MS). The developed method was validated according to the procedure given in the United States Food and Drug Administration guideline on the validation of bioanalytical methods. Validation parameters included limit of detection (≤ 0.03 μg g), limit of quantification (≤ 0.08 μg g), linearity (r ≥ 0.9998), intra-day and inter-day accuracy (86-110%) and precision (≤ 10%), extraction recovery (89-110%), carry-over effect and sensitivity. In addition, special attention was paid to the study of chromium species interconversion and the elimination of spectral interferences. Moreover, the validated ICP-MS method employing microwave acid digestion was used to determine the total Cr content in collected fractions. Finally, the whole ICP-MS-based methodology was applied to the analyses of two certified reference materials of hepatopancreas tissue. Obtained results indicated that the majority of chromium in biological tissues is bound to the solid residue, Cr(VI) was determined in none of the samples investigated. This is the first study focusing on soluble Cr(III), total Cr(VI), and total bound Cr species in biological tissues. It is characterized by efficient sample preparation and fast simultaneous analysis of Cr species with parallel total Cr analysis serving for chromium balance evaluation.
本工作提出了一种新颖的分析 ICP-MS 方法，用于准确、精密地对生物组织中的铬形态进行分析。采用碱性 EDTA 提取，随后采用离子交换高效液相色谱-电感耦合等离子体质谱（IE-HPLC-ICP-MS）对总 Cr(VI)和可溶性 Cr(III)形态进行分离和测定。该方法按照美国食品和药物管理局关于生物分析方法验证指南进行了验证。验证参数包括检出限（≤0.03μg·g）、定量限（≤0.08μg·g）、线性（r≥0.9998）、日内和日间精密度（86%-110%）和准确度（86%-110%）、提取回收率（89%-110%）、交叉污染效应和灵敏度。此外，特别关注了铬形态相互转化的研究和光谱干扰的消除。此外，还采用微波酸消解的 ICP-MS 法对收集的各馏分中的总 Cr 含量进行了测定。最后，将整个基于 ICP-MS 的方法应用于两种肝脏组织标准物质的分析。结果表明，生物组织中的大部分铬与固体残渣结合，在所研究的样品中均未检测到 Cr(VI)。这是首次针对生物组织中的可溶性 Cr(III)、总 Cr(VI)和总结合态 Cr 进行的研究。该方法具有高效的样品前处理和快速同步分析 Cr 形态的特点，同时进行总 Cr 分析以评估铬平衡。
