New American National Standards developed by the Society for Biomolecular Screening (SBS), an ANSI member and accredited standards developer, affect the design of microplates used in drug discovery and other testing, and are expected to support more efficient, cost-effective early-stage drug discovery.
A microplate is a plastic plate, or cassette, containing a number (typically 96 or 384) of small wells arranged in rows. According to the PolyPops Development Foundation, almost all microplates are made from various plastics and polymers, while some of the new innovative plates incorporate optical grade glass, fiberglass matting, a range of filter membranes and specialty papers. Microplates are used to conduct a number of chemical reactions at the same time, and serve as essential tools used in drug discovery research.
Each well in a microplate contains a tiny amount of a compound to be tested, combined with a reagent. By gauging the subsequent effect on the reagent, a judgment can be made about a compound's potential value and effectiveness against a particular target biological system or disease. The microplate allows for a high volume of compounds to be assayed rapidly and efficiently in a process called “biomolecular screening.” Using microplates that meet a common standard streamlines the process by ensuring compatibility across systems.
"Until now, if a scientist ran a screen, he or she had to program the instrument for every microplate. We might have, for example, 100 different types of 96-well microplates, each slightly different from the other," explained Carol Ann Homon, Co-Chair of SBS' Microplate Standards Development Committee (MSDC). "Now we can be sure that if plates meet the ANSI/SBS standards, results will be consistent across platforms, and costs to laboratories will be reduced."
The standards proposed by the MSDC and approved by ANSI/SBS are: ANSI/SBS 1-2004: Footprint Dimensions; ANSI/SBS 2-2004: Height Dimensions; ANSI/SBS 3-2004: Bottom Outside Flange Dimensions; and ANSI/SBS 4-2004: Well Positions (the fourth standard addresses 96, 384, and 1536 well density formats, which are presently considered to be the platform for 98% of the screening assays). The four ANSI/SBS standards apply to all microplates, without regard to their plastic composition.
The MSDC is now working on two additional standards, one that addresses microplate side-wall rigidity and another that addresses the "flatness" of well bottoms that are critical for use with imaging devices and other automated equipment.
SBS is dedicated to drug discovery and its related disciplines, and provides a forum for global education and information exchange among professionals in the chemical, pharmaceutical, biotech, and agrochemical industries.