Huang Shiqi, Zhang Limin, Dai Liyi, Wang Yuanyuan, Tian Yang
School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, P. R. China.
Anal Chem. 2021 Apr 6;93(13):5570-5576. doi: 10.1021/acs.analchem.1c00151. Epub 2021 Mar 23.
There is still an urgent need to develop reliable analytical methods of O in vivo for deeply elucidating the roles of O playing in the brain. Herein, a nonenzymatic electrochemical sensor with ratiometric signal output was developed for an in vivo analysis of O in the rat brain. Diphenylphosphonate-2-naphthol ester (ND) was designed and synthesized as a specific recognition molecule for the selective determination of O. An anodic peak ascribed to the oxidation of 2-naphthol was generated via the nucleophilic substitution between ND and O and was increased with the increasing concentration of O. Meanwhile, the inner reference of methylene blue (MB) was co-assembled at the electrode surface to enhance the determination accuracy of O. The anodic peak current ratio between 2-naphthol and MB exhibited a good linear relationship with the concentration of O from 2 to 200 μM. Because of the stable molecule character of ND and its specific reaction with O, the developed electrochemical sensor demonstrated excellent selectivity toward various potential interferences in the brain and good stability even after storage for 7 days. Accordingly, the present electrochemical sensor with high selectivity, high stability, and high accuracy was successfully exploited in monitoring the levels of O in the rat brain and that of the diabetic model followed by cerebral ischemia.
仍然迫切需要开发可靠的体内O分析方法，以深入阐明O在大脑中所起的作用。在此，开发了一种具有比率信号输出的非酶电化学传感器，用于大鼠大脑中O的体内分析。设计并合成了二苯基膦酸酯-2-萘酚酯（ND）作为选择性测定O的特异性识别分子。通过ND与O之间的亲核取代反应产生了一个归因于2-萘酚氧化的阳极峰，并且该峰随着O浓度的增加而增大。同时，亚甲基蓝（MB）内参比物共组装在电极表面，以提高O的测定准确性。2-萘酚与MB的阳极峰电流比与2至200μM的O浓度呈现良好的线性关系。由于ND的分子特性稳定及其与O的特异性反应，所开发的电化学传感器对大脑中各种潜在干扰物表现出优异的选择性，并且即使储存7天后仍具有良好的稳定性。因此，这种具有高选择性、高稳定性和高精度的电化学传感器成功用于监测大鼠大脑中O的水平以及糖尿病模型脑缺血后的O水平。
