MICROFABRICATION OF ALKYLSILANIZED GLASS SUBSTRATE BY ELECTROGENERATED HYDROXYL RADICAL USING SCANNING ELECTROCHEMICAL MICROSCOPY

Scanning electrochemical microscopy (SECM) was used for localized elec trogeneration of hydroxyl radical to create patterns with diaphorase o n the substrates immobilized with self-assembled monolayers (SAMs) of four different alkylsilane derivatives. Hydroxyl radical was generated at an SECM tip (microelectrode) in a solution containing H2O2 and Fe3 + by applying a reduction potential pulse of 0.00 V vs Ag/AgCl. The el ectrogenerated hydroxyl radical degraded the SAMs and removed them fro m the glass surfaces. Diaphorase patterns were formed on the substrate s by physical adsorption onto the hydrophobic area or by chemical link age to the hydroxyl radical-attacked area. Local diaphorase activity w as visualized by SECM by detecting the diaphorase-catalyzed current of ferrocenylmethanol coupled with oxidation of reduced nicotinamide ade nine dinucleotide.