Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Heilongjiang Province; College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin, 150025, People's Republic of China.
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, Harbin Normal University, Harbin, 150025, People's Republic of China.
Mikrochim Acta. 2019 Aug 5;186(9):604. doi: 10.1007/s00604-019-3710-4.
Fluorescent carbon dots co-doped with nitrogen and sulfur (N/S CDs) were prepared and found to display viable peroxidase mimicking activity. They have a blue fluorescence (with excitation/emission maxima at 340/456 nm) with a quantum yield of 35%. The N/S CDs catalyze the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of HO, and this leads to the appearance of a blue solution with a absorption maximum at 654 nm. A colorimetric method was developed for the determination of HO that has a 1.75 μM detection limit and a linear response in the 10 to 10 M concentration range. The method can be extended to the enzymatic determination of glutathione with a 0.26 μM detection limit and a working range from 0.20 to 100 μM. In addition, the CDs respond to lead(II) which is a quencher of the blue fluorescence at 456 nm, with a detection limit of 11 μM and a working range up to 100 μM. Simultaneously, the color changes can be visually detected with absorbance signal changes from 10 to 100 μM with limit of 3.9 μM. A multiple detection system was worked out that allows monitoring of HO and glutathione successively, and of lead(II). Graphical abstract (A) Schematic representation of the nitrogen & sulphur doped carbon dots with blue fluorescence, (B) the peroxidase-like activity in colorimetric detecting of HO and GSH and (C) the illustration for the application of Pb detection with fluorescence and colorimetric method.
氮硫共掺杂荧光碳点（N/S CDs）被制备出来，并被发现具有可行的过氧化物酶模拟活性。它们具有蓝色荧光（激发/发射最大值为 340/456nm），量子产率为 35%。N/S CDs 在 HO 的存在下催化 3,3,5,5-四甲基联苯胺（TMB）的氧化，这导致出现蓝色溶液，其吸收最大值在 654nm。建立了一种用于测定 HO 的比色法，其检测限为 1.75μM，在 10 到 10 M 的浓度范围内具有线性响应。该方法可扩展用于测定谷胱甘肽的酶法，其检测限为 0.26μM，工作范围为 0.20 至 100μM。此外，碳点对铅（II）有响应，铅（II）是 456nm 处蓝色荧光的猝灭剂，检测限为 11μM，工作范围可达 100μM。同时，可以通过吸收信号从 10 到 100μM 的变化来肉眼检测到颜色变化，其检测限为 3.9μM。设计了一个多重检测系统，可以成功地监测 HO 和谷胱甘肽的顺序以及铅（II）。
