Effect of Electrophoresis on the Efficiency of Graphite-Nano-TiO2 Modified Silica Sol-Gel Electrode.

Electrophoresis treatment was used to improve the function of a nano-TiO2 modified sol-gel electrode. Electrodes were prepared using TiO2 nanoparticles and fine graphite powder and then treated by electrophoresis. The developed electrode was employed for the detection of lactate dehydrogenase (LDH) by following the decrease in the immobilised lactate peak current due to its LDH-mediated enzymatic oxidation. Detection was realised using square wave voltammetry (SWV). Experiments showed that the positive and negative heads of the electrophoresis-treated electrode displayed different activities, with the positive head response being remarkably improved. Parameters affecting the electrode response, such as applied potential value, electrophoresis time and percentage of TiO2, were investigated and optimised. The improved performance was dependent on TiO2 concentration as well as electrophoresis voltage and time. The prepared sensor, under optimised conditions, displayed a detection limit of 0.0073 U/μl for LDH.