AGGLUTINATION REACTION DEVICE HAVING GEOMETRICALLY MODIFIED CHAMBERS

2100365 9208972 PCTABS00013 Disclosed is a device for performing agglutination reactions comprising: in adherent relationship, a first wettable layer (1), a second liquid-occlusive layer (2) parallel to and overlying the first layer (1), and a third layer (3) parallel to and overlying the second layer (2) and having a window for observing particles. The second layer is interposed between, and is in adherent relationship to the first and third layers. The second layer (2) has at least one general slot (25) defining a channel for directing liquid conducted by capillary action through a chamber defined by the slot in conjunction with the first (1) and third (3) layers. The chamber has a proximate zone and a distal zone. The geometry of the chamber is modified to provide flow paths having different rates of flow per unit area along the paths. This arrangement of such different paths in the chamber allows agglutination reactions in the chamber to result in the formation of a non-random pattern of aggregated particles in the distal zone of the chamber. Such a non-random pattern is more readily observable than a random pattern of aggregated particles.