School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, 19A YuQuan Road, Beijing 100049, PR China.
School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, 19A YuQuan Road, Beijing 100049, PR China.
Talanta. 2018 May 1;181:318-325. doi: 10.1016/j.talanta.2018.01.027. Epub 2018 Jan 11.
A highly sensitive and selective detection of hexavalent chromium (Cr(VI)) and ascorbic acid (AA) was proposed using nitrogen-doped carbon dots (N-CDs). In the absence of AA, the quantitative detection of Cr(VI) was realized through Cr(VI) acting as a quencher to quench the fluorescence of N-CDs by inner filter effect (IFE) and static quenching effect. Under the optimal conditions, the linear range for Cr(VI) detection was from 0.01 to 250μM with a detection limit of 5nM (S/N = 3). In the presence of AA, the fluorescence intensity could be rapidly enhanced compared with the fluorescence of N-CDs/Cr(VI) system since Cr(VI) can be reduced into trivalent chromium (Cr(III)) by AA. And a wide linear range for AA detection was obtained from 1 to 750μM. The detection limit was 0.3μM (S/N = 3). More importantly, this method can be successfully applied to the detection of Cr(VI) in real water samples, and AA in vitamins C tablets and human serum sample.
本文提出了一种利用氮掺杂碳点（N-CDs）对六价铬（Cr(VI)）和抗坏血酸（AA）进行高灵敏度和选择性检测的方法。在不存在 AA 的情况下，通过 Cr(VI)作为内滤光效应（IFE）和静态猝灭效应的猝灭剂来猝灭 N-CDs 的荧光，实现了对 Cr(VI)的定量检测。在最佳条件下，Cr(VI)的检测线性范围为 0.01 至 250μM，检测限为 5nM（S/N = 3）。在存在 AA 的情况下，与 N-CDs/Cr(VI)体系的荧光相比，荧光强度可以迅速增强，因为 AA 可以将 Cr(VI)还原成三价铬（Cr(III))。并且，AA 的检测线性范围很宽，从 1 至 750μM。检测限为 0.3μM（S/N = 3）。更重要的是，该方法可成功应用于实际水样中 Cr(VI)和维生素 C 片剂及人血清样品中 AA 的检测。
