Device for magnetically assisted binding assays

A device is provided for determining the presence or amount of an analyte in a test sample. The device comprises (a) at least one channel through which a reaction mixture can flow; (b) a magnetic field generator for applying a magnetic field to the components in said reaction mixture; and (c) a measurement means to assess the effect of the magnetic field generated by the magnetic field generator on the components of the reaction mixture as a measure of the presence or amount of analyte in the test sample. Assays methods using such devices utilize the response of a magnetically responsive reagent to the influence of a magnetic field to qualitatively or quantitatively measure binding between specific binding pair members.