Abstract: A device for simultaneously performing multiple biochemical or immunological reactions. A manifold plate rests atop a waste fluid collection chamber or receptacle suitable for attachment to a vacuum pump. The manifold contains a series of wells that serve as reaction vessels. The sides of each well are fluid-impermeable, and its lower end provides a planar, annular base. A hydrophobic membrane is sealed to the lower surface of the base of each well. The membrane is formed of a material through which fluid can be drawn upon application of vacuum while retaining the fluid within the well in the absence of vacuum. By placement of a solid-phase support for binding biological coreactants atop the membrane prior to initiation of the reaction, solid-phase reaction products can be collected when vacuum is applied and can then be freely withdrawn from its well.

Abstract: Apparatus is provided for automatically scanning electronically each well of a multi-well tray containing many liquid samples. A light source, preferably a single source, is passed through the wells to an array of photosensitive cells, one for each well. There is also a calibrating or comparison cell receiving the light. Electronic apparatus reads each cell in sequence, quickly completing the scan without physical movement of any parts. The resultant signals are compared with the signal from the comparison cell and with other signals or stored data and determinations are made and displayed or printed out. Thereby, and by the methods of the invention, such matters as minimum inhibitory concentrations (MIC) of drugs and identification of microorganisms are achieved.