Chang H C, Ueno A, Yamada H, Matsue T, Uchida I
Department of Molecular Chemistry and Engineering, Faculty of Engineering, Tohoku University, Japan.
Analyst. 1991 Aug;116(8):793-6. doi: 10.1039/an9911600793.
Amperometric determination of nicotinamide adenine dinucleotide (reduced form) (NADH) at an immobilized-diaphorase (Dp) electrode is described. The measurement was conducted using ferrocenylmethanol as a mediator in a stirred solution at 0.20 V versus a saturated calomel electrode. A linear relationship between the steady-state current and the concentration of NADH was found over the range 0.005-0.125 mmol dm-3. The immobilized-Dp electrode showed outstanding stability and the current response reached a steady state within 2-3 seconds upon addition of NADH. The proposed electrode was used to follow the reactions of pig heart lactate dehydrogenase and horse liver alcohol dehydrogenase. The kinetic investigation using the immobilized-Dp electrode gave the kinetic parameters (Michaelis constants, Km values, and maximum velocities, Vm values), which were in satisfactory agreement with those determined by a conventional spectrophotometric method.
描述了在固定化黄递酶（Dp）电极上安培法测定烟酰胺腺嘌呤二核苷酸（还原型）（NADH）。测量是在搅拌溶液中，以二茂铁基甲醇作为媒介体，相对于饱和甘汞电极在0.20 V下进行的。在0.005 - 0.125 mmol dm⁻³范围内，发现稳态电流与NADH浓度之间呈线性关系。固定化Dp电极表现出出色的稳定性，加入NADH后，电流响应在2 - 3秒内达到稳态。所提出的电极用于跟踪猪心乳酸脱氢酶和马肝醇脱氢酶的反应。使用固定化Dp电极进行的动力学研究给出了动力学参数（米氏常数、Km值和最大速度、Vm值），这些参数与通过传统分光光度法测定的参数令人满意地一致。
