Artificial Dialysis Membranes: From Concept to Large Scale Production

Abstract

The development of hemodialysis from an experimental concept to a routine medical therapy is closely related to research, manufacturing and availability of dialysis membranes. Collodion, a cellulose-trinitrate derivative, was the first polymer to be used as an artificial membrane and played a central role in further investigations and applications. Basic studies on the mechanism of solute transport through membranes, like diffusion, were done by A. Fick and T. Graham using collodion as a membrane material. In vivo dialysis in animals and humans was performed with collodion by J. Abel in the USA and G. Haas in Germany. Cellophane and Cuprophan membranes replaced collodion later, because of their better performance and mechanical stability. However, due to its alleged lack of hemocompatibility, membranes made from unmodified cellulose lost their market share. They have been replaced by modified cellulosic and synthetic dialysis membranes which show a better hemocompatibility than unmodified cellulose membranes. Most of the new membrane materials are also available in high-flux modifications and for this reason suitable as well for more effective therapy modes, such as hemodiafiltration and hemofiltration. The success of hemodialysis as a routine therapy is also the success of membrane development, because both, a reproducible membrane production and an unlimited availability of dialysis membranes have increased the number of dialyzed patients to about 1 million patients worldwide in 1999.

Cytotoxic effects exerted by polyarylsulfone dialyser membranes depend on different sterilization processes

“…Control values were taken as 100%. Data are expressed as the mean ± SD from at least three independent experiments the most versatile polymer types used for the manufacture of modern dialysis membranes are clearly those belonging to the polyarylsulfone family of polymers, comprising PSu which is an established membrane material with a 20-year history of clinical experience, and PAES that has recently been introduced in clinical practice [28]. However, the membrane sterilization processes are thought to induce toxic effects in HD patients, either directly or indirectly, via inflammatory reactions.…”

Developments in extracorporeal therapy for the poisoned patient

“…German and French chemists are credited with developing collodion, which was known as guncotton because of its tendency to explode at high temperature, from nitrocellulose dissolved in ether and ethyl alcohol [1]. Adolph Fick published his work on the passive movement of solute across membranes as a result of differences in concentration soon after Graham [2]. Fig.…”

“…The total length of the tubing was 756 cm, 2 cm in diameter with total membrane surface area of 1.53 cm 2 [2]. But collodion membranes were fragile and needed to be prepared just in time, their porosity depending on how long the material was soaked in alcohol [1,6].…”

Bioartificial Kidney

“…[23][24][25] A major limitation of current membrane technology is diminution of filtration rate owing to protein deposition on the membrane and thrombotic occlusion of the hollow fibers. Modern membranes are used reliably all over the world in countless HD, HF, and HDF procedures.…”