An L-lactate sensor with immobilized enzyme for use in in vivo studies with an endocrine artificial pancreas.

We report the features of a sensor for determining L-lactate. An oxygen sensor, coupled to a nylon net with chemically bound L-lactate oxidase (EC 1.1.3.2), is inserted into an artificial pancreas (Biostator, Miles) "downstream" from the glucose sensor. We used the sensor to continuously monitor the L-lactate concentration in blood after a "glucose clamp" experiment with a diabetic patient. L-Lactate determinations in blood drawn from the patient every 15 min agreed well with results obtained by use of the L-lactate sensor.