Improvement of the Microtiter Hemagglutination Method

Abstract

A sensitive method of hemagglutination in disposable Microtiter plates was described, using small amounts of polyvinylpyrrolidone (PVP), Tween 80, and protein to promote red cell settling in the plastic wells. Although the PVP and Tween did not alter the specificity of the agglutination systems tested (ABO and Rh), they could conceivably interfere with others. We now report that it is possible to dispense with the PVP and Tween (but not protein) if the plates are coated prior to use with a thin, smooth layer of paraffin. This is accomplished by dipping the plates in a clear solution of 2 parts of toluene: 1 part melted Bioloid Paraffin Embedding Compound* at 55–60 C. Thereafter the plates are immediately shaken in a vigorous manner at least 10 times to get rid of the excess solution, and then are placed upside down and allowed to dry overnight. The paraffin coating is at first soft, but a hard even coat is left behind on the plates after the toluene has evaporated. 1968 AABB