Immunoassay systems

Buying guide

The measurement chemistry a platform is built around decides more than any throughput figure, because it sets what the instrument can detect at all. A reader built for colorimetric ELISA cannot run a chemiluminescent assay, and a fluorescence-based bead system reads panels that an absorbance analyser never will. Confirm which detection modes a unit supports, which wavelengths or channels it covers, and whether the assays your protocols depend on have been validated on it. On a multiplex platform, the number of simultaneous analytes it can resolve per well is the figure that separates one generation of instrument from the next, and it is worth matching that to the panels you actually run rather than the maximum the datasheet advertises.

A used analyser carries history that the specification sheet does not. Optical components drift, light sources age, and fluidics in automated immunoassay systems accumulate wear that affects pipetting accuracy. Ask for the most recent calibration record, the lamp or laser hour count where the platform tracks it, and confirmation that the wash and aspiration lines were serviced. For bead-based and chemiluminescent systems, verify that the detector still meets its original sensitivity specification, since a weak signal path quietly widens every result. Where a listing includes validation or qualification documentation, that record is worth more than the instrument's age, because immunoassay instrumentation is judged on measured performance, not on year of manufacture.

Price here spans a wide band, and the range reflects the gap between a bare microplate reader and a fully automated clinical chemistry line. Prices run from EUR 16 to EUR 116.220. What a unit costs tracks closely with automation and detection breadth: manual plate readers sit at the low end, while walk-away analysers with integrated sample handling occupy the top. A buyer working to a fixed budget will find that a refurbished benchtop reader covers routine ELISA work at a fraction of a new platform's price, since refurbished units listed for sale are more affordable than new ones. Among the dominant names, Charles River, Bio-Rad, Luminex, PerkinElmer, ProteinSimple appear most often, which matters for a buyer because an installed base makes consumables, replacement parts and like-for-like comparison easier. Parts can be sourced via Questpair when a listing arrives incomplete.

Types of Immunoassay systems

Which immunoassay system types are listed?

Among the listings that specify a type, the catalogue groups into a handful of distinct instrument classes, each built for a different stage of the assay workflow. An immunoassay analyzer is the general term for a benchtop or floor-standing unit that runs the binding reaction and reads the result, and it is the most common entry here. A microplate reader measures signal from the wells of a standardised plate, by absorbance, fluorescence or luminescence, and is the workhorse of plate-based ELISA. A microplate washer handles the wash steps between reagent additions, removing unbound material so the final read is clean. Clinical chemistry analyzers overlap with this category where a single instrument runs both immunoassays and routine chemistry panels. At the automated end sit automated immunoassay systems and automated immunoassay analyzers, which add robotic sample handling, onboard reagent storage and walk-away operation for high-volume laboratories.

These instruments do the quantitative measurement work behind immunoassay and ELISA, and that places them across much of molecular diagnostics. A microplate reader performs the readout step in immunoassay development and in protein quantitation; a bead-based analyser does multiplex immunoassay for cytokine and biomarker panels in proteomics and cell biology. Platforms of this class are also used for drug screening in bioprocessing and for antibody characterisation in molecular biology. The clinical chemistry analyzers listed here serve haematology-adjacent and endocrine testing, where hormone and protein immunoassay panels run alongside routine chemistry. Where a laboratory works in biomanufacturing or cell culture monitoring, these same readers quantify secreted proteins and titres from culture supernatant.

The brands behind the immunoassay system listings

The names that recur most across these listings are Charles River, Bio-Rad, Luminex, PerkinElmer, ProteinSimple. For a buyer, a strong presence of a given maker is practical rather than reputational: it means more comparable units on the catalog at any one time, a deeper pool of compatible consumables, and a better chance of sourcing a replacement optical module or fluidics part. Bead-based multiplex platforms and plate readers each carry their own assay ecosystems, so matching a used instrument to the reagent kits a laboratory already validates against saves far more than the purchase price gap. Describing each company belongs on its own brand page; here, what matters is availability and how easily one model can be weighed against another.

What a used immunoassay system costs here

99 percent of the listings are used. Prices run from EUR 16 to EUR 116.220, and that spread covers everything from a standalone microplate washer to a fully automated clinical analyser. Refurbished and used units are listed below the price of equivalent new instruments, which is the one firm comparison the catalogue data supports. Where a buyer needs to weigh a used unit against a new one, the individual listing is the place to check condition and documentation, and a warranty can be arranged in consultation for that specific listing.