Electrochemical Patterning of Self-Assembled Monolayers onto Microscopic Arrays of Gold Electrodes Fabricated by Laser Ablation

This report demonstrates proof-of-concept application of two established electrochemical techniques affecting self-assembled monolayers the thermodynamic control of monolayer assembly at gold and the electrochemical desorption of self-assembled monolayers from gold to pattern monolayers onto gold microelectrodes. When combined with a simple laser-based microfabrication technique, using commercially available microscope adaptations, to form arrays of individually-addressable gold microelectrodes from continuous thin gold films on glass, two new patterning methodologies result that enable fabrication of monolayer-based affinity arrays for potential use in chemical and biosensors. The described microfabrication technique is central to the success of these patterning methodologies because it allows SAM patterning of metal arrays immediately after their fabrication, so as to avoid problems associated with forming SAMs on commercially-supplied arrays. In this paper, each patterning methodology is used to fabricate an interdigitated microelectrode array in which one set of electrodes is modified with an active antibody and the other set of electrodes is resistant to nonspecific protein adsorption.