Biospecific multiparameter assay method

Claim 1

A biospecific multiparameter assay method based on the use of different categories of microspheres, each different category representing a different analyte to be assayed and comprising an amount of an internal fluorescent dye with short decay time sufficient to provide fluorescence that is measurably different from each other different category, each different category of microspheres being coated with a different biospecific reactant, said method comprising the steps of pooling the different categories of microspheres together in a suspension, and adding the sample containing analytes to be assayed and a mixture of labelled biospecific reactants that bind to the analytes of interest into the suspension to initiate biospecific reactions between the analytes and the labelled reactants and microsphere-associated reactants, diluting the suspension to reduce the concentration of labelled reactants not bound to the microspheres, exciting the internal fluorescent dye and measuring he strength of the emitted fluorescence, and converting the fluorescence emissions to electrical signals and identifying the category of each microsphere on the basis of the strength of the electrical signal resulting from the short decay time fluorescent dye, characterized by the label of the biospecific reactant being a phosphorescent metalloporphyrin and for each identified category of microspheres determining the concentration of the analyte bound to a microsphere of said category by measuring the strength of the electrical signal resulting from the photon emissions generated by the phosphorescent label on said microsphere.