US Patent 6913935 Multiple assay method

A method for the assay of N samples each containing a compound to be tested, comprises providing N reaction vessels each containing a population of carrier beads and other reagents for performing the assay, where N is at least 2 e.g. 80-4000. Each population of carrier beads is distinguishable from every other population. After adding the samples to the reaction vessels and performing the assays, the contents of all the reaction vessels are mixed and subjected to analysis by flow cytometry. By means of flow cytometry, each carrier bead is rapidly analysed to identify its population and also to determine the presence or concentration or biological activity of the compound to be tested.