|Daniel Rhinow1 and Norbert Hampp1,2
1Faculty of Chemistry, University of Marburg, Hans-Meerwein-Straße, 35032 Marburg, Germany
2Material Science Center Marburg, D-35032 Marburg, Germany
Microarray technology is a rapidly developing field and a powerful tool in genome and proteome analysis and drug screening. Surface patterning methods are still a key challenge in the field of ‘biochip’ fabrication. Self-assembled monolayers (SAMs) of alkanethiols on gold surfaces are widely used in nanotechnology and serve as templates for the immobilization of biomolecules.
We present a process, named submerged laser ablation (SLAB), which enables the preparation of complex patterned SAMs, free gold areas suitable as electrodes, and in addition laser patterning of the substrate itself in a single process.[1,2]
A template-stripped gold (TSG) substrate, is first covered with a SAM of a thiol (primary thiol). The assembly is then submerged into a solution of a second thiolated compound (secondary thiol or reactant). The laser beam incidents the TSG by passing through the reactant solution and the SAM formed by the first thiol. The area of gold surface where the laser beam hits is heated due to the partial absorption of the laser light. The primary thiol is released from the surface in the direction of the laser beam movement. As soon as the laser beam proceeds, the surface temperature decreases and the secondary thiol fills in from the supernatant, by forming covalent bonds with the TSG.