Abstract NADH plays a vital role in the electron transfer processes between metabolites in the cellular energetic reactions. Therefore, there is a crucial need to develop analytical techniques for detecting NADH levels with the metabolism of glucose. In the present study, a nanocomposite of alumina (Al2O3) nanoparticles confined graphene oxide (GO) sheet acts as a modifier for carbon paste electrode (CPE) for a sensitive detection of NADH level in a mediator-less detection scheme. Our findings after optimization of experimental conditions reveal that, there is a remarkable enhancement in the direct electron transfer through the Al2O3-GO nanocomposite surface with high electrocatalytic activity towards NADH oxidation. Results show that, there is a linear increase in NADH detection from 30 µM to 330 µM, together with linear regression coefficient of 0.98 and LOD 4.5 µM. These results confirm that, the developed Al2O3-GO based CPE electrode is a promising electrode for real NADH level detection in practical enzymatic applicability.

中文翻译：

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Al 2 O 3 -GO纳米复合修饰电极电化学检测二氢烟酰胺腺嘌呤二核苷酸

摘要 NADH 在细胞能量反应中代谢物之间的电子转移过程中起着至关重要的作用。因此，迫切需要开发通过葡萄糖代谢检测 NADH 水平的分析技术。在本研究中，氧化铝 (Al2O3) 纳米颗粒限制氧化石墨烯 (GO) 片的纳米复合材料充当碳糊电极 (CPE) 的改性剂，用于在无介质检测方案中灵敏检测 NADH 水平。我们在优化实验条件后的发现表明，通过 Al2O3-GO 纳米复合材料表面的直接电子转移显着增强，对 NADH 氧化具有高电催化活性。结果表明，NADH 检测从 30 µM 线性增加到 330 µM，连同线性回归系数 0.98 和 LOD 4.5 µM。这些结果证实，开发的基于 Al2O3-GO 的 CPE 电极是一种很有前途的电极，可用于实际酶促应用中的真实 NADH 水平检测。