title: Electrochemical evaluation of lactate dehydrogenase immobilized in polyacrylamide gels.
abstract: Lactate dehydrogenase (EC 1.1.1.27) has been immobilized in polyacrylamide gels over a platinum grid matrix. The immobilized enzyme is used to oxidize L-lactate in the presence of nicotinamide adenine dinucleotide (NAD+) and ferricyanide. The NADH produced is then chemically oxidized back to NAD+ by ferricyanide. The coupled reduction of ferricyanide ions to ferrocyanide ions results in a measurable electrochemical potential. This measurable zero-current potential is found to be Nernstian in nature and directly proportional to the logarithm values of L-lactate concentration over the range of 2 X 10(-5) to 5 X 10(-2)M. The results indicate that immobilized lactate dehydrogenase can be incorporated into a system to detect L-lactate acid in aqueous solutions.
mesh_terms: D000178:Acrylamides; D000818:Animals; D002417:Cattle; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005782:Gels; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D009206:Myocardium / Q000201:enzymology
chemical_list: D000178:Acrylamides; D004800:Enzymes, Immobilized; D005782:Gels; D007770:L-Lactate Dehydrogenase