Abstract: The multichannel capillary biosensor system includes a selecting valve system for selection of the sample or a reagent. The selecting valve system is connected to a second valve system accommodating a sensing channel and a first bypass channel. The second valve system is connected to a directing valve system having at least two positions, with a first position being connected to a second bypass channel and a second position being connected to a detector for detecting the analyte. The device has a pump connected at one end to the second bypass channel and the detector and at a second end to a waste vessel. The device also has a control system for controlling the device. The analyte can be selected from the group of microorganisms, macromolecules, and small molecules.