Automated immunoanalyzer system for performing diagnostic assays for autoimmune and infectious diseases

A method of performing a diagnostic assay, comprising:

• a) combining a capture reagent-coated separation medium, wherein the separation medium comprises fluorescently-labelled particles, with an analyte-containing sample in a reaction cuvette, wherein the capture reagent has been biotinylated with PEG12-Biotin and the fluorescently-labelled particles have been coated with streptavidin;
• b) binding luminescent labels to the separation media in proportion to a number of bound analyte molecules, to form a complex;
• c) measuring an initial fluorescent signal associated with an initial quantity of the fluorescently-labelled particles;
• d) washing the complex;
• e) adding a luminescing reagent or substrate to the cuvette to generate a luminescent signal in proportion to the number of bound analyte molecules,
• f) measuring the luminescent signal and a final fluorescent signal associated with a final quantity of the fluorescently-labelled particles in the cuvette;
• and
• g) normalizing the luminescent signal by a ratio of initial fluorescent signal to final fluorescent signal to calculate a reported value.