J. Berthier, M. Cubizolles, P. Laurent, P. Pouteau, V. Poher, M-L. Cosnier
pp. 137 - 140
Keywords: bi-substrate enzymatic reaction, Michaelis-Menten, glucose sensor
Colorimetric detection of glucose in sample liquids such as human plasma is made by using enzymatic reactions. In the multi reactional scheme, the first enzymatic reaction is determinant. Either glucose oxidase (GOX) or glucose dehydrogenase (GDH) can be used to convert glucose. We focused here on the study of the enzyme GDH together with the enzymatic cofactor NAD (nicotinamide adenine dinucleotide). The reaction can be written as: Beta-D-glucose+NAD+GDH <-> glucono-lactone+NADH+GDH This reaction falls in the category of ternary enzymatic reactions. Such reactions depend on four parameters. In order to optimize the reaction, these parameters must be first determined. A method to determine these four parameters is presented in this work, based on a comparison between a series of experiments and the theory. The best values of the parameters are indicated.