Patent ID: 6770489
Filing Date: 2004-08-03
Classification: G01N

Abstract:
A method for immunoassay with a magnetic material label, the method comprising:(1) preparing an analyte labeled with said magnetic material label; (2) applying said analyte labeled with said magnetic material label, to an antigen fixed to a support so that said analyte is bounded to said antigen by means of an antibody/antigen reaction; (3) magnetizing said magnetic material label on said analyte bounded to said antigen, by a magnetic field, thereby forming a magnetized magnetic material labeled analyte; and (4) while continuing to apply said magnetic field which magnetizes the magnetic material label, detecting the magnetized magnetic material labeled analyte by sensing, by using a Superconducting Quantum Interference Device, a magnetic flux component which is generated from said magnetized magnetic material labeled analyte and which is at a right angle to the direction of said magnetic field which magnetizes said magnetic material label.