NADH oxidase (NOX) is an oxidoreductase that catalyzes the oxidation of NADH to NAD⁺ with the participation of oxygen. NOX can artificially regulate metabolic processes as an important regulatory enzyme for NAD⁺ regeneration. In this study, cobalt-doped molybdenum sulfide (Co-MoS₂) nanocomposite was prepared by hydrothermal synthesis, which exhibited NOX mimics. The catalytic mechanism of NOX mimics was studied. The NOX-like activity of Co-MoS₂ is optimal at pH 4.5 and in the temperature range of 20–45℃. Further, its catalytic activity maintained almost the same after 5 cycles of repetitive addition of NADH, suggesting that Co-MoS₂ nanozyme possessed significant catalytic persistence. The produced H₂O₂ catalyzed by Co-MoS₂ can be detected by horseradish peroxidase (HRP) and 3,3′,5,5′-tetramethylbenzidine at pH4.5. Thus, interestingly, a colorimetric NADH sensor was proposed on the basis of the enzymatic cascade reaction of NADH oxidase-like conjugated with HRP. This as-established method had wide detection range (0.5–800 μM) with the detection limit of 0.25 μM NADH, capable of detecting NADH in real sample.

NADH氧化酶（NOX）是一种氧化还原酶，在氧的参与下催化NADH氧化为NAD ⁺。NOX作为NAD ⁺再生的重要调控酶，可以人为调控代谢过程。在这项研究中，钴掺杂的硫化钼 (Co-MoS ₂ ) 纳米复合材料是通过水热合成制备的，其表现出 NOX 模拟物。研究了NOX模拟物的催化机理。Co-MoS ₂的类NOX 活性在pH 4.5 和20-45℃的温度范围内最佳。此外，在重复添加 NADH 5 个循环后，其催化活性几乎保持不变，表明 Co-MoS ₂纳米酶具有显着的催化持久性。产生的 H₂ Ó ₂的Co-MOS催化₂可以通过辣根过氧化物酶（HRP）和3,3'，在pH4.5时5,5'-四甲基联来检测。因此，有趣的是，基于与 HRP 结合的 NADH 氧化酶样的酶促级联反应，提出了比色 NADH 传感器。这种已建立的方法具有较宽的检测范围（0.5-800 μM），检测限为 0.25 μM NADH，能够检测实际样品中的 NADH。