Design and optimization of a lactate amperometric biosensor based on lactate oxidase cross-linked with polymeric matrixes

MARCELO RICARDO ROMERO; FERNANDO GARAY,; ANA M. BARUZZI

ELSEVIER SCIENCE SA

Año: 2008 vol. 131 p. 190 - 190

he design and characterization of a lactate biosensor is described. The biosensor is developed through the immobilization of lactate oxidase(LOD) in an albumin and mucin composed hydrogel. The enzyme is then cross-linked with glutaraldehyde to the polymeric matrix and entrappedbetween two polycarbonate membranes. The hydrogen peroxide produced by the reaction of lactate andLODis detected on a Pt electrode operated at0.65V versus Ag|AgCl. The performance of the biosensor was evaluated in matrixes with different amounts of albumin, mucin and glutaraldehyde.The response time of the sensor to 10 M lactate required 90 s to give a 100% steady-state response of 0.079 A. Linear behavior was obtainedfor 0.7 M<cLac < 1.5 mM. The detection limit calculated from the signal to noise ratio was 0.7 M. Only 0.1U of enzyme was necessary to geta biosensor with a relatively high current flow and an excellent stability over a storage period of 30 days. High repro