Here we report on a facile, rapid, selective, and stable electrochemical sensing platform for nicotinamide adenine dinucleotide (NADH) based on polythionine-methylene blue/electrochemically reduced graphene oxide modified glassy carbon electrode (PTH-MB_DES-ERG/GCE). The ERG was directly formed on a glassy carbon electrode (ERG/GCE) through one-step electrochemical reduction of GO in PBS solution (10 mM, pH 7.4). In a PBS electrolyte, respectively, containing 50% (v/v) three different deep eutectic solvents (DES), thionine and methylene blue were polymerized on the surface of ERG/GCE. The electrochemical properties of the polymers polymerized in different electrolytes were investigated. The PTH-MB_DES-ERG composite has a higher performance in the electrocatalytic oxidation of NADH than that of PTH-MB_DES. The as-prepared PTH-MB_DES-ERG/GCE demonstrated excellent direct electrocatalytic oxidation toward NADH, providing a favorable platform for electron transfer from NADH to the electrode. The sensor displayed a wide linear range from 1.52 μM to 3333.33 μM with a limit of detection of 0.51 nM. The interference from the ascorbic acid and uric acid was negligible. The prepared sensor was further tested for the determination of NADH in artificial urine samples, showing the PTH-MB_DES-ERG/GCE formed by electropolymerization have promising biomedical applications.

在这里，我们报告了一种基于聚硫氨酸-亚甲蓝/电化学还原氧化石墨烯改性玻碳电极 (PTH-MB _DES -ERG/GCE) 的简便、快速、选择性和稳定的烟酰胺腺嘌呤二核苷酸 (NADH) 电化学传感平台。通过在 PBS 溶液（10 mM，pH 7.4）中一步电化学还原 GO，ERG 直接在玻碳电极（ERG/GCE）上形成。在分别含有 50% (v/v) 三种不同深共熔溶剂 (DES) 的 PBS 电解质中，亚硫氨酸和亚甲蓝在 ERG/GCE 表面聚合。研究了在不同电解质中聚合的聚合物的电化学性能。PTH-MB _DES-ERG复合材料对NADH的电催化氧化性能优于PTH-MB _DES。所制备的 PTH-MB _DES -ERG/GCE 对 NADH 表现出优异的直接电催化氧化，为从 NADH 到电极的电子转移提供了有利的平台。该传感器显示出从 1.52 μM 到 3333.33 μM 的宽线性范围，检测限为 0.51 nM。抗坏血酸和尿酸的干扰可以忽略不计。进一步测试制备的传感器用于测定人工尿液样品中的NADH，表明通过电聚合形成的PTH-MB _DES -ERG/GCE具有广阔的生物医学应用前景。