Thermal stability of diazonium derived and thiol-derived layers on gold for application in genosensors

DNA analysis using variable temperature technologies such as melting curve analysis, high temperature mutant discrimination or immobilised PCR relies upon the use of immobilised probes that need to be stable over a wide temperature range. In this work a comparison of the thermal stability of gold surfaces modified with alkanethiol and diazonium salt derived layers is presented. Electrochemical impedance spectroscopy and cyclic voltammetry were used to characterize the electrode arrays. The applicability of the surfaces for DNA sensing was demonstrated following the thermal treatment, with the diazonium-modified surface being markedly more stable. (C) 2010 Elsevier B.V. All rights reserved.