Microtiter plate (microplate)

Formats and standards

Microplates are manufactured in a variety of well counts to suit different throughput needs. Common formats include:

• 6-, 12- and 24-well plates for larger volume assays and cell culture
• 48- and 96-well plates as general laboratory standards
• 384- and 1536-well plates for high-throughput screening where reagent use must be minimized

Most plates share a standardized footprint so they fit readers, washers and robotic handlers; industry standards such as ANSI/SLAS define dimensions and plate features to ensure compatibility.

Materials and well shapes

Plates are made from plastics chosen for optical clarity, chemical resistance, or temperature tolerance. Typical materials include polystyrene (optically clear, often used for absorbance and fluorescence), polypropylene (chemical- and temperature-resistant, used for storage and PCR), and polycarbonate (durable). Wells come in shapes such as flat-bottom, round-bottom and V-bottom; surface treatments or coatings (e.g., tissue-culture treated, hydrophobic) adapt plates to cell attachment or biochemical binding.

Detection of reactions in microplates is accomplished with plate readers and other instruments that measure absorbance, fluorescence, luminescence or time-resolved signals. Sealing films, lids and careful temperature control are commonly used to limit evaporation and contamination during incubation or measurement.

Microplates emerged as laboratory automation and immunoassay techniques developed; they became central to ELISA (enzyme-linked immunosorbent assay) workflows and later to high-throughput screening in drug discovery. Today they are ubiquitous across clinical diagnostics, basic research, biotechnology, and industrial testing.

Advantages include parallel processing, reduced reagent consumption and easy integration with automated liquid-handling systems. Practical considerations when using microplates include evaporation (especially in peripheral wells), edge effects, cross-contamination, proper sealing, and selecting the right plate material and well geometry for the assay chemistry and detection method.