Abstract: A device for concentrating and/or purifying macromolecules in liquids is disclosed wherein the concentration/purification is accomplished by a membrane separating concentration and filtration chambers, the membrane and chambers being compressively held in fluid-tight relationship by sliding engagement with a sleeve-like housing. A method for assembling such a device is also disclosed.

Abstract: An improvement in the fabrication and bonding of dead-end and cross-flow thermoplastic filtration modules is disclosed whereby two housing parts are bonded to each other and to a filtration membrane by an L-shaped plastic melt.

Abstract: A device for removing or replacing solvent in a liquid sample containing macromolecules includes a concentration chamber having an aperture adjacent to the upper end of the concentration chamber which is arranged to receive and tightly fix the outlet of a detachable auxiliary reservoir. In methods employing the device, the concentration chamber is filled with part of a liquid sample to a predetermined level, and a detachable auxiliary upper reservoir containing the rest of the liquid sample is tightly fixed to the aperture adjacent to the upper end of the concentration chamber to successively deliver additional liquid sample as the concentration is progressing, or a detachable auxiliary upper reservoir containing a solvent or buffer solution is tightly fixed to the aperture adjacent to the upper end of the concentration chamber to successively deliver solvent or buffer solution as a replacement for the liquid absorbed by an absorption material.