Wang Xiufeng, Jin Yao, Ai Wenhui, Wang Siqi, Zhang Zhiqing, Zhou Ting, Wang Fang, Zhang Guodong
Department of Chemistry, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China.
Department of Chemistry, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2024 Feb 15;307:123626. doi: 10.1016/j.saa.2023.123626. Epub 2023 Nov 7.
Near infrared (NIR) emission AgS quantum dots (QDs) are of great value for biochemical sensing with strong anti-interference and low toxicity. Herein, NIR fluorescence AgS QDs were synthesized successfully. Combined with the excellent oxidase-like characteristics of manganese dioxide (MnO) nanosheets, a fluorescence and colorimetric dual-mode sensor for sulfide anion was developed. MnO nanosheets could effectively catalyze the oxidation of TMB to produce blue TMB oxide (ox TMB), at the same time, the fluorescence of AgS QDs could be effectively quenched by fluorescence internal filtration effect (IFE) and dynamic quenching effect. The enzyme-like activity was weakened and the NIR fluorescence of AgS QDs was restored when sulfide anion (S) was added, due to the reduction of MnO to Mn.The linear ranges for fluorescence and colorimetric analysis of S were 2-250 μM and 0.3-50 μM, with detection limits of 0.6 and 0.215 μM, correspondingly. The dual-mode sensor had a wider detection range, higher sensitivity and shorter reaction time, which could be used for highly selective detection of S in different concentration ranges. In addition, it had been successfully applied to the determination of sulfide in water samples with satisfactory accuracy and sensitivity.
近红外（NIR）发射的硫化银量子点（QDs）在生化传感方面具有重要价值，具有很强的抗干扰能力和低毒性。在此，成功合成了近红外荧光硫化银量子点。结合二氧化锰（MnO）纳米片优异的类氧化酶特性，开发了一种用于检测硫化物阴离子的荧光和比色双模式传感器。MnO纳米片可以有效地催化TMB氧化生成蓝色的氧化TMB（ox TMB），同时，硫化银量子点的荧光会因荧光内滤效应（IFE）和动态猝灭效应而被有效猝灭。当加入硫化物阴离子（S）时，由于MnO被还原为Mn，类酶活性减弱，硫化银量子点的近红外荧光恢复。S的荧光和比色分析的线性范围分别为2 - 250 μM和0.3 - 50 μM，检测限分别为0.6和0.215 μM。该双模式传感器具有更宽的检测范围、更高的灵敏度和更短的反应时间，可用于在不同浓度范围内对S进行高选择性检测。此外，它已成功应用于水样中硫化物的测定，具有令人满意的准确度和灵敏度。
