ELISA Plates

Quick Answer: ELISA Plates are microplates, usually 96-well and made of clear polystyrene, whose well surface binds proteins so that antigens or antibodies can be fixed to it for enzyme-linked immunosorbent assays. ELISA plates are read in a microplate reader after a colour-forming enzyme reaction has developed in each well.

How an ELISA Plate Works

An ELISA begins by coating the wells: a solution of antigen or capture antibody is left in the plate, and the protein sticks to the polystyrene. Remaining binding sites are then blocked with an unrelated protein, samples are added, and a series of antibody and washing steps builds up an enzyme-labelled complex in wells where the target is present. A substrate such as TMB turns blue in proportion to the enzyme bound, the reaction is stopped with acid, and absorbance is read, commonly at 450 nm.

The plate surface decides how well proteins stick. Medium-binding surfaces suit larger, more hydrophobic proteins, while high-binding surfaces are treated to hold a wider range of antibodies and antigens more strongly. Plates come as solid 96-well plates or as frames holding removable 8- or 12-well strips, which let a lab run only as many wells as it has samples. The binding level and format of this listing are not stated in the title.

Flat-bottomed wells give an even light path for the reader. These plates are not interchangeable with tissue culture plates, which are treated for cell attachment, or with the Micro Test Plates, which are used for agglutination and dilution tests. Clear plates are used for colorimetric ELISA; white or black plates are used when the signal is luminescent or fluorescent.

Specifications

Getting Consistent Results

• Keep unused strips sealed in their pouch, with desiccant if supplied, to protect the surface
• Cover plates with a sealing film during incubations to prevent evaporation
• Wash wells thoroughly and consistently, tapping the plate dry on paper towel between steps
• Avoid touching the well bottoms, since fingerprints affect absorbance readings

Applications

• Sandwich and indirect ELISA for detecting antibodies or antigens in serum
• Teaching immunology practicals on antigen-antibody binding
• Screening sera for antibody titre after immunisation
• Quantifying cytokines or hormones against a standard curve in research labs

Why Choose LabEquip

Immunology and microbiology departments, diagnostic training labs and research groups developing or running immunoassays are the main buyers. LabEquip supplies ELISA plates in Biology Lab Products; tell us the binding type and strip or solid format you need through our contact page.

Frequently Asked Questions

What is the difference between an ELISA plate and a cell culture plate?

An ELISA plate surface is treated to bind proteins passively, which is what an immunoassay needs. A cell culture plate is treated for cells to attach and grow and is supplied sterile, so the two are not interchangeable.

What is the difference between medium and high binding plates?

Medium binding plates hold larger, more hydrophobic proteins well. High binding plates are treated to capture a wider range of proteins, including smaller or more hydrophilic ones, and are the usual choice for antibody coating.

Why use strip plates instead of solid plates?

Strip plates let you break off and use only the wells you need, which saves plates when sample numbers are small. Solid plates are sturdier and suit full-plate runs and automated washers.

At what wavelength are the plates read?

That depends on the substrate. TMB, the most common, is read at 450 nm after stopping with acid, often with a reference wavelength around 570 or 630 nm to correct for plate imperfections.

Can the plates be washed and reused?

No. Coated proteins, blocking agents and bound antibodies cannot be removed reliably, and the surface changes after use, so the plates are single-use.

Do the plates need to be sterile?

Generally not, because an ELISA does not grow cells. Clean, dust-free handling still matters, and plates should be kept sealed until they are coated.

Last Updated: September 2026