Potential-pulse assisted thiol chemisorption minimizes non-specific adsorptions in DNA assays

Abstract

Effective suppression of non-specific adsorption is crucial for high-sensitive DNA hybridization sensors. Thiol-based passivation layers as generally used in DNA sensors often exhibit insufficient surface blocking and hence additional blocking agents are used to fully protect the surface from non-specific adsorption. We demonstrate that potential pulse-assisted thiol self-assembly on gold electrodes as surface passivation step in DNA assays provides minimized non-specific adsorption as evidenced by chronoamperometric and SECM measurements. Fast and highly efficient surface blocking is achieved avoiding the necessity of additional blocking steps.