Abstract: A buffer solution being used in an electrophoresis cell as both an electrode buffer and a cooling medium is circulated through a refrigeration system external to the cell without risk of arcing or other danger despite the electrified state of the buffer solution. The refrigeration system contains a circulating coolant, a shell-and-tube heat exchanger, various components for the coolant such as a compressor, condenser and capillary, and preferably also a by-pass which, on command from a temperature control unit, passes warm coolant from the compressor discharge directly to the heat exchanger. Couplings of dielectric material insulate the heat exchanger from the remaining components of the refrigeration system.

Abstract: A plate assembly for performing multiple filtrations with the use of a vacuum offers advantages for small samples due to the construction of its component plates, which include an upper plate with apertures forming sample wells, a membrane sheet forming the floor of each well, a collection plate with individual wells underneath the membrane sheet, aligned with the upper plate apertures, and a drop guide plate between the membrane sheet and the collection plate to guide and force small quantities of liquid downward from the membrane into the collection wells. The arrangement permits extremely small quantities of species on the membrane to be drawn into the collection wells without dilution, and avoids cross contamination between collection wells.

Abstract: An electrophoresis apparatus for use with horizontally disposed separation media is disclosed, comprised of a housing with lid, and removable components capable of applying an electric potential across a horizontally disposed medium, the components adapted for electrification by plugless electrical connections each of which establishes firm electrical contact with a power supply upon mere placement of the components in the housing. In its various embodiments, the apparatus is adapted to apply the potential through the use of electrified buffer solutions, electrified wires for placement in direct contact with the separation medium, or both. Spring-loaded contacts on either the buffer solution receptacles or the electrified wires mate with exposed power strips in the housing to form the connection.