Patent ID: 6228602
Filing Date: 2001-05-08
Classification: C12Q,G01N

Abstract:
An assay for an analyte in a fluid test sample which comprises combining the fluid test sample with a peroxide and a redox dye, together with an apo-peroxidase or apo-pseudoperoxidase and a metal porphyrin which is bound to an analyte/analyte specific binding partner complex, said complex having a combined molecular weight of at least about 180 K Daltons which is sufficiently high to prevent reconstitution of the apo-peroxidase or apo-pseudoperoxidase and metal porphyrin in the absence of analyte but will allow such reconstitution in the presence of analyte in the fluid test sample due to interaction between the analyte in the fluid test sample and the analyte specific binding partner portion of the complex which disrupts the complex to thereby reduce the molecular weight of the analyte/analyte specific binding partner complex bound to the metal porphyrin to less than that level at which the reconstitution of the apo-peroxidase and metal porphyrin is inhibited so that the apo-peroxidase and its corresponding metal porphyrin can reconstitute to form an active peroxidase which will interact with the peroxide and the redox dye at a pH of from about 1 to 12 to provide a colored response.