title: Electrochemical characterization of immobilized NAD+.
abstract: Nicotinamide adenine dinucleotide (NAD+) has been covalently attached to alginic acid using carbodiimide coupling, thereby producing a macromolecular adduct of NAD, which can be rendered either soluble or insoluble by adjustment of pH. It was found that this NAD+-alginic acid complex was enzymatically active, and also that the oxidized form could be electrochemically reduced without loss in enzymatic activity. This NAD+ adduct has now also been polarographically characterized as to its two-step reduction waves, which are slightly shifted toward more cathodic potential as compared to free NAD+. When controlled electrolysis was conducted to reduce the bound NAD+ at the cathode, the NADH so formed by electrochemical action was found to be again oxidizable either enzymatically or electrochemically without loss in co-enzymatic function. The NADH adduct produced by electrochemical reduction of the NAD+ adduct has also been characterized by voltammetry.
mesh_terms: D000464:Alginates; D001665:Binding Sites; D002234:Carbodiimides; D008722:Methods; D009243:NAD / Q000032:analysis*; D010084:Oxidation-Reduction; D011048:Polarography; D012995:Solubility; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000464:Alginates; D002234:Carbodiimides; D009243:NAD