多脉冲安培法-碳纤维微电极测定亚硝酸盐的抗污染方法。

Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes, 748, São Paulo 05513-970, SP, Brazil.

Molecules. 2023 Jan 2;28(1):387. doi: 10.3390/molecules28010387.

Nitrite is a ubiquitous pollutant in modern society. Developing new strategies for its determination is very important, and electroanalytical methods present outstanding performance on this task. However, the use of bare electrodes is not recommended because of their predisposition to poisoning and passivation. We herein report a procedure to overcome these limitations on carbon fiber microelectrodes through pulsed amperometry. A three-pulse amperometry approach was used to reduce the current decay from 47% (after 20 min under constant potential) to virtually 0%. Repeatability and reproducibility were found to have an RSD lower than 0.5% and 7%, respectively. Tap water and synthetic inorganic saliva samples were fortified with nitrite, and the results obtained with the proposed sensor were in good agreement with the amount added.

亚硝酸盐是现代社会中无处不在的污染物。开发新的测定方法非常重要，电化学分析方法在这一任务上表现出色。然而，由于裸电极容易中毒和钝化，因此不建议使用裸电极。本文报道了一种通过脉冲安培法克服这些限制的方法。采用三脉冲安培法，将电流衰减从 47%（在恒电位下 20 分钟后）降低到几乎为 0%。发现重复性和重现性的 RSD 分别低于 0.5%和 7%。自来水和合成无机唾液样品中加入了亚硝酸盐，用所提出的传感器得到的结果与添加的量吻合良好。