A device, method and system for measuring analytes in a solution or suspension. The device includes a housing, a sample chamber, one or more pumps, one or more detectors, one or more stirrers, electrical contacts, a magnetic manipulator and a lid. A sample cartridge for a device that measures analytes, the cartridge comprising a first outer compartment, a second outer compartment, and a middle compartment, wherein the first outer compartment and the second outer compartment are interconnected to the middle compartment by channels.