Automatic apparatus for immunological assay

Automatic immunological assay apparatus, comprising:

• (a) at least one module comprising a plurality of longitudinally juxtaposed reaction wells;
• (b) means for providing at least one sample to be analyzed;
• (c) means for providing at least one magnetic bead reagent;
• (d) means for introducing determined quantities of sample and reagent into a reaction well;
• (e) means for reading assay results;
• (f) an open loop track comprising fixed elements, which track supports and guides the modules;
• (g) a chain or belt that extends along the track and engages the modules to move the modules from an upstream end of the track to a downstream end of the track;
• (h) automatic module feed means and module ejection means being provided respectively at the upstream end and at the downstream end of said track;
• (i) means for moving the reaction wells stepwise in a downstream direction past the means for introducing sample and reagent and the means for reading the results;
• and
• (j) two magnetic bead washing heads respectively disposed at separate positions on opposite branches of the track for washing magnetic beads contained in reaction wells of a module positioned under the respective washing head, with both washing heads being movable between a first, rest position, and a second, working position, and being carried by a common support for vertical displacement between the two positions,
• wherein the means for reading assay results comprises two systems for optically reading assay results, said systems being spaced apart from each other on the track with a first of the two systems being adapted for reading the results of single-reagent type assays and a second of the two systems being adapted for reading the results of dual-reagent type assays.