Agglutination reaction device utilizing selectively impregnated porous material

A device for performing simultaneously a plurality of agglutination reactions comprising:

• in adherent relationship, a first hydrophilic layer, a second layer parallel to and overlying said first layer, and a third layer parallel to and overlying said second layer and having windows for observing agglutinated particles, said second layer interposed between and in adherent relationship to said first and third layers, said second layer comprising a liquid-absorbent material selectively impregnated with a substance to form an impregnated region and a plurality of non-impregnated regions wherein said non-impregnated regions are liquid-absorbent and said impregnated region is liquid-occlusive, said second layer including means defining a plurality of slots in radial spatial relationship to each other in said impregnated region and defining channels for directing liquid conducted by capillary action through chambers defined by said slots in conjunction with said first and third layers and within which chambers agglutination reactions can be performed simultaneously, each of said chambers having a proximate zone and a distal zone and means for controlling overall rate of liquid flow through said chamber, said means for controlling comprising a non-impregnated region of said second layer which non-impregnated region is in liquid communication with said chamber and wherein a portion of the non-impregnated impregnated region is positioned within the distal zone of said chamber.