Abstract: A method of detecting first and second analytes includes providing a mixture containing first analytes and second analytes; adding microparticles of a first size coated with first competitive inhibitors that compete with the first analytes for binding to first antibodies to the first analytes, and adding microparticles of a second size coated with second competitive inhibitors that compete with the second analytes for binding to first antibodies to the second analytes, adding second antibodies specific to the first antibodies to the first analytes and second antibodies specific to the first antibodies to the second analytes, wherein the second antibodies specific to the first antibodies to the first analytes are labeled with a first fluorescent moiety, and the second antibodies specific to the first antibodies to the second analytes are labeled with a second fluorescent moiety

Abstract: Compositions and methods are provided for analyzing a sample for the presence or absence of one or more target analytes. Microparticles bound to an analyte of interest are incubated in a solution containing a primary antibody directed towards the analyte. In direct assays of this invention, the microparticle-bound analyte competes with a labeled primary antibody do displace analyte from the primary antibody. Primary antibodies can be labeled with florescence or other labels detectable using a flow cytometer. The microparticle-bound analyte-primary antibody complex can be detected and quantified using a flow cytometer. In other, indirect assays, an unlabeled primary antibody can be used, and a labeled secondary antibody can react with a microparticle-bound analyte-primary antibody complex to form a labeled microparticle-bound analyte-primary antibody complex. The labeled microparticle-boudn alalyte-primary antibody complex can be detected using a flow cytometer.

Abstract: A method of detecting analytes includes providing a mixture containing analytes to be analyzed and microparticles coated with competitive inhibitors of the analytes. First antibodies are reacted with the analytes and the competitive inhibitors under competitive binding conditions. The first antibodies bound to the competitive inhibitors are measured using flow cytometry.

Abstract: Compositions and methods are provided for analyzing a sample for the presence or absence of one or more target analytes.

Abstract: Compositions and methods are provided for analyzing a sample for the presence or absence of one or more target analytes.