A device (1) for sensing an analyte, the device (1) comprises at least a sample inlet (10) for receiving a sample, affinity probes (111) selected to have a preferential binding to the analyte, a transducer (11) sensitive to a characteristic of the analyte and/or a label attached to the analyte, the transducer not being a FET transducer, and a desalting unit (13) for desalting the received sample.