Berdat, D.Rodriguez, A. C. MartinHerrera, F.Gijs, M. A. M.2008-01-162008-01-162008-01-16200810.1039/B712609Chttps://infoscience.epfl.ch/handle/20.500.14299/16270WOS:000252758100014We investigate the analytical performance of an interdigitated electrode sensor for the label-free detection of DNA, by monitoring the complex impedance of 5 µm wide interdigitated Pt microelectrodes on a glass substrate. We detect the hybridization of unlabeled 38-mer target ssDNA with a complementary probe that is bound on the glass in between the electrodes by a disuccinimidyl terephtalate and aminosilane immobilization procedure. The sensor is mounted in a microfluidic flow cell, in which hybridization is monitored and in situ compared with a reference. After hybridization, the cell is perfused with deionised water and the dependence of the measured conductance due to the immobilized target DNA layer, to target DNA concentrations down to 1 nM is demonstrated. Subsequently, we apply our sensor to the detection of pathogen DNA from Salmonella choleraesuis in dairy food.text::journal::journal article::research article