Electrodes Potentiometriques Et Amperometriques a Levures Permeabilisees: Determination Du L-Lactate

Publisher Website
Google Scholar
Abstract
A biosensor using permeabilized yeasts (Hansenula, anomala) was described for the determination of L-lactate. The same electrode can be used either potentiometrically or amperometrically. The linear ranges were respectively of 4.10-5 M-2.10-3 M for potentiometry and 8.10-7 M-3.10-3 M for amperometry with reproducibility and a precision of .+-. 2-3%. The parameters involved in the optinization of electrode response, such as pH, temperature, cofactor concentration and ionic strength of the buffers, were discussed in details for both types of measurements. The amperometric technique was suitable for lactate determinations in biological media. In this case, differential measurements were used in order to eliminate interferences of biological redox reactions.