Wang Shengwen, Shi Yu, Zhang Hao, Sun Yufeng, Wang Fangfang, Zeng Leyong, Li Xing, Wu Aiguo, Zhang Yujie
School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, China; Cixi Institute of Biomedical Engineering, International Cooperation Base of Biomedical Materials Technology and Application, CAS Key Laboratory of Magnetic Materials and Devices and Zhejiang Engineering Research Center for Biomedical Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences (CAS), Ningbo 315201, China; Advanced Energy Science and Technology Guangdong Laboratory, Huizhou 516000, China.
Cixi Institute of Biomedical Engineering, International Cooperation Base of Biomedical Materials Technology and Application, CAS Key Laboratory of Magnetic Materials and Devices and Zhejiang Engineering Research Center for Biomedical Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences (CAS), Ningbo 315201, China; Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Chemical Biology Key Laboratory of Hebei Province, College of Chemistry & Environmental Science, Institute of Life Science and Green development, Hebei University, Baoding 071002, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2023 Jul 5;295:122589. doi: 10.1016/j.saa.2023.122589. Epub 2023 Mar 9.
Hexavalent chromium (Cr(VI)) is highly carcinogenic and mutagenic, which is seriously harmful to human health. Hence, it is important to create a probe that can detect Cr(VI) effectively. In this work, gold nanotetrapods (Au NTPs) were applied in colorimetric detection for the first time. Based on the oxidative etching principle of Cr(VI) on Au NTPs, a sensitive and multicolor response detection method for Cr(VI) was established. The oxidative etching of Au NTPs by Cr(VI) resulted in the blue shift of plasmon resonance absorption peak of Au NTPs with the change of morphology. As the etching progress processed, Au NTPs solution exhibited obvious color changes from gray-green to blue-violet and then to pink. This multicolor response design is very convenient for naked-eye detection. The limit of detection (LOD) of Cr(VI) is 3 nM for the naked eyes and 0.5 nM for UV-vis spectrum, both of which are lower than the toxicity level of Cr(VI) (0.2 μM) set by United States Environmental Protection Agency. This sensing method exhibits good linearity between the wavelength shift and Cr(VI) concentration in the range of 0.5 nM to 8 nM. The detection results of Cr(VI) in actual environmental samples demonstrate that the Au NTPs colorimetric probe (Au-N-Probe) is expected to be applied to the detection of Cr(VI) in water environmental samples such as lake water and industrial wastewater.
六价铬（Cr(VI)）具有高度致癌性和致突变性，对人体健康危害极大。因此，开发一种能够有效检测Cr(VI)的探针具有重要意义。在本研究中，首次将金纳米四脚体（Au NTPs）应用于比色检测。基于Cr(VI)对Au NTPs的氧化蚀刻原理，建立了一种灵敏的Cr(VI)多色响应检测方法。Cr(VI)对Au NTPs的氧化蚀刻导致Au NTPs的表面等离子体共振吸收峰发生蓝移，同时形态也发生变化。随着蚀刻过程的进行，Au NTPs溶液呈现出明显的颜色变化，从灰绿色变为蓝紫色，再变为粉红色。这种多色响应设计非常便于肉眼检测。Cr(VI)的肉眼检测限（LOD）为3 nM，紫外可见光谱检测限为0.5 nM，均低于美国环境保护局设定的Cr(VI)毒性水平（0.2 μM）。该传感方法在0.5 nM至8 nM范围内，波长位移与Cr(VI)浓度之间呈现出良好的线性关系。实际环境样品中Cr(VI)的检测结果表明，金纳米四脚体比色探针（Au-N-Probe）有望应用于湖水和工业废水等水环境样品中Cr(VI)的检测。
