Abstract: A centrifugal rotor effects the isolation, in a sequence of steps, of a substance from a mixture of substances dissolved, suspended or dispersed in a sample liquid. Multiple samples are processed simultaneously by means of a plurality of fractionation cells, each of which contains a series of interconnected, chambered and vented compartments in which individual steps of the fractionation and isolation procedure take place. Specific steps in the preferred embodiments include lysis, sedimentation, aggregation, sorption, rinsing, and desorption. The specific compartment occupied by the sample liquid or one of its fractions at any stage of the process is governed by the speed and direction of rotation of the rotor and by gravitational force. The interconnections, chambers and passages of each compartment are sized and angled to prevent predetermined amounts of sample and reagent liquids from overflowing the compartment.

Abstract: The apparatus comprises electrophoresis chamber (1) with positioned therein along the sides of a rectangle electrode groups (2,3,4,5) of equidistantly positioned electrodes. One pair of subtending electrode groups (2,4) is connected to power supply (8), the other pair of subtending electrode groups (3,5) is connected to power supply (10) via switch (9).

Abstract: An apparatus has an electrophoretic chamber in which groups of electrodes are positioned along sides of an equilateral quadrangle. Electrodes within each group are positioned in equally spaced relation to one another and are connected to a power supply via a switching circuit.

Abstract: An apparatus and process is provided for an electrophoretic determination the primary structure of nucleic acids. The apparatus comprises a cuvette shaped as a sleeve having a gel shaped as a hollow cylinder positioned on one of the side surfaces of the sleeve and having samples of the nucleic acid in recesses on its end face located in a circle. The sleeve is provided with a rotation drive and its side wall and the bottom together with the side wall and the bottom of the second sleeve mounted coaxially with the first sleeve form chambers for placing electrode solutions therein. Between the electrode solutions in the region between the side walls of the sleeves there is located a non-polar liquid, its density is higher than that of the electrode solution located above it and lower than the density of the electrode solution located thereunder.