Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering , Northwest Normal University , Lanzhou 730070 , People's Republic of China.
Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science , Tianjin University , Tianjin 300072 , People's Republic of China.
Anal Chem. 2018 Dec 18;90(24):14309-14315. doi: 10.1021/acs.analchem.8b03597. Epub 2018 Dec 5.
Hexavalent chromium ion (Cr) is one of the most toxic substances for plants, for animals, and is a confirmed human respiratory carcinogen. However, so far, there are few independent and efficient colorimetric methods for detection of Cr. Here, we introduce a convenient, label-free, catalysis-based, and efficient strategy for quantification of Cr by using a colorimetric sensing probe 3,3',5,5'-tetramethylbenzidine (TMB). In the presence of a trace amount of gold amalgam nanocomposites (Au@Hg) and Cr, TMB can be oxidized to oxTMB and the color changed to an intense blue that was observed by naked-eye and absorption spectroscopic method. In addition, the colorimetric method shows the high selectivity against 34 other interfering substances, and it can be performed at room temperature, in water, and requires only ∼5 min. Thus, the catalysis-based colorimetric assay for accurate and ultrahigh selective identification of Cr will find widespread use in the world.
六价铬离子（Cr）对植物、动物具有毒性，被确认为人类呼吸道致癌物。然而，目前针对 Cr 的检测方法很少具有独立性和高效性。在这里，我们引入了一种方便、无标记、基于催化且高效的策略，使用比色传感探针 3,3',5,5'-四甲基联苯胺（TMB）定量检测 Cr。在痕量金汞合金纳米复合材料（Au@Hg）和 Cr 的存在下，TMB 可被氧化为 oxTMB，颜色变为强烈的蓝色，可通过肉眼和吸收光谱法观察到。此外，比色法对 34 种其他干扰物质具有高选择性，可在室温、水中进行，且仅需约 5 分钟。因此，基于催化的比色分析方法可用于准确、超高选择性识别 Cr，将在全球范围内得到广泛应用。
