The bienzyme electrodes were fabricated by coimmobilization of lactate oxidase (LOD) and lactate dehydrogenase (LDH) onto electrochemically prepared polyaniline (PANI) films. These PANI/LOD/LDH bienzyme electrodes were shown to provide signal amplification by substrate recycling, making it possible to detect L-lactate at lower concentrations (0.1-1 mM). The PANI/LOD/LDH bienzyme electrodes were found to be stable for about 21 d at 4-10 degreesC.