Agglutination method for the determination of multiple ligands

A method for determining the presence or absence of each of a predetermined number of a plurality of different ligands in a liquid, semi-liquid or pasty specimen, by a direct or indirect agglutination, or an agglutination inhibition method by competition, comprising the steps:

• contacting the specimen with a predetermined plurality of homogenous populations of fluorescent beads having a specific fluorescence and one or more predetermined antiligands fixed to their surface, said predetermined plurality of populations being less than said predetermined number of ligands and wherein at least one of said ligands is capable of binding to the antiligand on two or more of said homogeneous populations of beads;
• when said predetermined number of ligands;
• analyzing said specimen containing said beads using a measuring means capable of discriminating between the specific fluorescence of said beads for each ligand;
• determining in response to said analyzing step, the number of non-agglutinated beads, the number of agglutinated beads, the number of bead aggregates and for each aggregate, the number of beads it comprises and the population type or types of beads it comprises;
• and
• correlating the information determined in said determining step with the presence or absence in said specimen of each of said different ligands to thereby enable the simultaneous determination of a plurality of ligands using a single bead contacting step.