Abstract: A bi-component microporous hollow fiber membrane structure is provided for in vivo propagation of cells and use in testing of the effect of medical treatments on cells within the structure. The structure has an inner structure fabricated from a first bio-compatible polymer and an outer structure fabricated from a different polymer that has a lower tendency for cell adhesion than the inner structure polymer. In this way, the inner structure can be selected to optimize cell propagation and the outer structure can be fabricated from a polymer which optimizes the removal of the bi-component structure from its implanted location. The inner and outer structures may have a pore size between 10 and 1000 Angstroms and 100 and 2000 Angstroms, respectively, and be formed from polysulfone or polyether sulfone and polyvinyledene difuoride, respectively. The membrane structure can form macrocapsules containing media and living cells for implanting.

Abstract: A microporous hollow fiber membrane structure for use in the in vivo testing of the effect of medical treatments on cells within the structure. The structure has an inner portion fabricated from a first bio-compatible polymer and an outer structure fabricated from a different polymer than the inner structure. In this way, the inner structure can be selected to optimize cell propagation and the outer structure can be fabricated from a polymer which optimizes the removal of the bi-component structure from its implanted location.

Abstract: A process for performing a dialysis operation. The operation is carried out by snapping a weighted clamp on one end of a length of dialysis tubing. The dialysis tubing is then filled with a liquid to be treated and an unweighted clamp is snapped on the other end thereof. The assembly is then suspended in a dialysis bath thereby floating in a generally vertical position.

Abstract: A multi-part assembly held together by a clamp. Two or more parts are held together by a clamp which fits into two grooves formed in the outer surface of a part to be clamped. The clamp has a bail which surrounds the clamped parts, and a flexible arm holds one of the parts and the bail holds the other of the parts.

Abstract: A vacuum filter funnel useful for separating solids from liquids. The funnel has a vacuum intake member which forms an airtight seal with a filtrate container, and also forms an airtight seal with an upper funnel member which has a perforated bottom. A threaded sleeve member fits within the upper funnel member and assists in holding the filter medium above the perforated bottom.

Abstract: A protein concentrator having a reservoir for holding a protein solution and a membrane positioned within the protein solution through which a portion of the solution passes. The membrane is held in the walls of a container assembly and a water soluble polymer is located on one side of the membrane to increase the concentration gradient through the membrane for concentrating the solution.