Target substance detection device and target substance detection method

Abstract

To detect a target substance accurately and effectively, a target substance detection deviceincludes: a liquid-sample introducing plateformed from a light-transmissive plate having a surface on which a liquid sample including a target substance and magnetic particles forming a conjugate with the target substance is introduced, and enabling propagating transmitted light of light irradiated from the rear face upward of the surface as propagated light; a rear face light irradiation unitconfigured to be able to irradiate the liquid-sample introducing platewith light from the rear face; a first magnetic field application unitdisposed on the side of the surface of the liquid-sample introducing plate, and configured to apply a magnetic field to move the conjugate in the liquid sample that is introduced on the surface of the liquid-sample introducing plate in the direction away from the liquid-sample introducing plate; and an optical-signal detection unitdisposed on the side of the surface of the liquid-sample introducing plate, and enabling detection of a change in optical signal based on the propagated light between before and after application of the magnetic field by the first magnetic field application unit