Goto Sota, Iwasaki Taiyo, Komori Kikuo
Graduate School of System Engineering, Kindai University, Takaya-Umenobe, Higashi-Hiroshima, 739-2116, Japan.
Department of Biochemistry and Chemistry, Kindai University, Takaya-Umenobe, Higashi-Hiroshima, 739-2116, Japan.
Anal Sci. 2025 Jul;41(7):989-996. doi: 10.1007/s44211-025-00776-y. Epub 2025 May 2.
Cup-stacked carbon nanofibers (CSCNFs), the surface of which provides highly ordered graphene edges and electroactive oxygen-containing functional groups, were investigated as electrode materials for oxidation of β-Nicotinamide adenine dinucleotide (NADH) at low overpotential. The NADH oxidation was facilitated at the CSCNF-modified glassy carbon (CSCNF/GC) electrode, the surface of which was electrochemically activated at -0.40 V (vs. Ag|AgCl) to generate electrochemically reduced electroactive oxygen-containing functional groups. The anodic peak current of NADH oxidation was observed at about + 0.065 V by cyclic voltammetry measurements. The obtained value was negatively shifted by ~ 0.33 and ~ 0.63 V compared with the CSCNF/GC electrode without the electrochemical reductive pretreatment and the GC electrode, respectively. In addition, NADH-dependent glucose dehydrogenase (GDH) molecule-modified CSCNF/GC electrodes enabled the detection of glucose at the low overpotential effectively in the presence of NAD, which accepts electrons from GDH and then reduces to NADH, after the electrochemical reductive pretreatment. Thus, the electrochemical reductive pretreatment of CSCNF electrodes would be useful for the development of highly sensitive NADH-dependent enzymatic biosensors.
杯状堆积碳纳米纤维（CSCNFs）的表面具有高度有序的石墨烯边缘和电活性含氧官能团，被研究用作在低过电位下氧化β-烟酰胺腺嘌呤二核苷酸（NADH）的电极材料。在CSCNF修饰的玻碳（CSCNF/GC）电极上，NADH的氧化得到促进，该电极的表面在-0.40 V（相对于Ag|AgCl）下进行电化学活化，以生成电化学还原的电活性含氧官能团。通过循环伏安法测量，在约+0.065 V处观察到NADH氧化的阳极峰电流。与未经电化学还原预处理的CSCNF/GC电极和GC电极相比，所得值分别负移了约0.33 V和0.63 V。此外，在进行电化学还原预处理后，NADH依赖性葡萄糖脱氢酶（GDH）分子修饰的CSCNF/GC电极能够在存在NAD的情况下在低过电位下有效地检测葡萄糖，NAD从GDH接受电子然后还原为NADH。因此，CSCNF电极的电化学还原预处理对于开发高灵敏度的NADH依赖性酶生物传感器将是有用的。
