Gyula Takatsy first created a microtiter plate (or microplate) in 1950. It had 6 x 12 wells and was made of plexiglass to run tests on the influenza virus. This invention paved a path by significantly improving and revolutionizing biomedical testing.
Eventually, the American National Standards Institute (ANSI) standardized the microplate’s dimensions, well designs, properties, and materials. This was done to improve the usability of microplates in a variety of applications.
Over time, the ANSI’s guidelines were adopted by suppliers so that scientists and medical professionals could work efficiently with automation and screening instruments and equipment.
What Are Microplates?
Microplates commonly used in biological, analytical, and clinical workflows are multi-well plates. They come in different sizes, materials, and finishes. So what are microplates used for? A microplate is used to measure the absorbance of volume-controlled samples to determine the concentration of nucleic acids and proteins.
What Are Microplates Made Of?
Several materials are used today to make microplates, with polystyrene being the most popular kind. The color of the microplate changes when introduced with titanium dioxide, allowing users to observe luminescence or absorbance. Likewise, it changes to black when carbon is added to biological assays for fluorescence testing.
To monitor temperature changes, manufacturers use polypropylene. Alternatively, quartz microplates are ideal for measuring precision temperature tests. It is also an ideal material to use when encasing rare compounds. Polycarbonate microplates are generally used as disposable plates since they’re preferred for DNA-related testing.
Why Are Microplates Important?
Microplates allow users to conduct multiple tests for accurate diagnostics and cost-effective batch testing. For scientists, microplates are as essential as the tests and samples they support from initiation to completion.
Microplates can withstand high temperatures, contain precise volumes, and remain stable through testing procedures. This makes microplates an essential accessory when used with analytical instruments. They can also be sterilized and reused if users procure the non-disposable variety. For these reasons, microplates have proved to be a cost-effective way of conducting tests.
Today, laboratories rely heavily on microplates such as a 96-well plate for its reliability, durability, and performance. It is commonly used in performing enzyme-linked immunosorbent assays (ELISAs), a gold standard of immunoassays to detect and identify antigens in a biomedical sample.
What Should Users Look for in Biological Assay Microplates?
Microplates must meet certain quality standards and performance protocols when used for biological assays. Here’s a list of what to look for:
- Low autofluorescence to avoid affecting an assay negatively
- Biological and chemical compatibility with assay reagents
- Ability to withstand and remain stable during humidity and fluctuating temperature conditions
- Ability to support the development, viability, and attachment of cells
- Even, flat surface
- Low absorption of biologicals and chemicals (low or non-binding surface)
- Ability to withstand different optical detection levels
- Leak-proof construction that won’t leach metals, solvents, or chemicals during testing
Laboratories must ensure that the required dimensions are shared with a manufacturer for optimal use with certain robotic handlers, microplate readers, and acoustic dispensing instruments. One of the most common distributors of microplates is Greiner Bio-One. In the manufacturing of these plates, strict guidelines are followed for production and lab distribution. These plates are now a standard piece of equipment available in most laboratories today.