A detector device: a source region (S), a drain region (D) and a gate contact (100) on a substrate (104), with a channel region between the source and drain regions (S, D), an insulator layer over the substrate, comprising vias (140, 142, 144) filled with conductor material, wherein the vias (140, 142, 144) are provided over the source, drain regions and a gate contact, an additional via (152) through the insulator layer, defining a first chamber leading to a first side of the channel region, a nanopore etched from this first chamber through the channel region, and connecting the first chamber to a second chamber, a drive means (60) for providing a voltage bias between the two chambers, a drive means for providing a voltage between the source and drain regions and gate, a current sensor (64) for sensing a charge flow between the source and the drain regions.