[O2 sensitive L-lactate biosensors with enzyme membranes based on L-lactate-2-monooxygenase and L-lactate-oxidase...

O2-sensitive biosensors using oxidase membranes have acquired considerable electro-analytical importance. Since some of these O2-converting enzymes also produce H2O2, the use of additive reagents for the O2-free breakdown of the H2O2 in the second reaction has repeatedly been reported. In contrast to L-lactate oxidase, L-lactate-2-monooxygenase converts its substrate without producing H2O2. Employing reference sera, tests with L-lactate showed that bioelectrochemical membrane electrodes with H2O2-producing enzymes of high purity, require no additive reagents to ensure reliable analysis. Continuous measurements with citrated blood using the principle of intermediate carrier analysis are demonstrated.