Nanostructured screen-printed electrodes based on titanate nanowires for biosensing applications.

This work demonstrates the successful modification of screen-printed electrodes using functionalized titanate nanowires for producing a peroxide biosensor. Titanate nanowires were synthesized by the hydrothermal method and characterized using physico-chemical techniques. The surface of the nanowires was modified with (3-aminopropyl)trimethoxysilane and glutaraldehyde to immobilize horseradish peroxidase through covalent bound, obtaining a surface coverage of 1.62mg of enzyme/m. The surface of screen-printed carbon electrodes was modified with peroxidase-containing nanowires. Cyclic voltammetry and chronoamperometry were employed to study the electrochemical properties of the nanostructured electrode. A low hydrogen peroxide reduction potential around -0.98V (vs Ag, pH7.0) was observed, with linear response in the range of 40 to 560μmolL, detection limit of 10.7μmolL and good stability. Reproducibility relative standard deviation was as low as 4.7%. For repeatability, deviation was 3.3%.