Artificial Cells for Artificial Kidney, Artificial Liver and Detoxification

Abstract

In 1956, while a premedical student at McGill, I prepared some artificial cells mainly to demonstrate the feasibility of the principle of “artificial cells” (Chang, 1957). Their use for artificial organs came later when on calculating the total membrane area available in artificial cells (semipermeable microcapsules) of different diameters very striking results were obtained (Chang, 1964, 1966). Thus, 10 ml of 20 micron diameter microcapsules or 33 ml of 100 micron diameter microcapsules have a total surface area of about 2.5 m2. Even 300 ml of very large microcapsules of 2 mm diameter have a total surface area of 2.5 m. What is more important is that membrane thickness of the microcapsules is 0.02 micron. This is 400 times thinner than the standard hemodialysis membrane. This large membrane area and the ultrathin membrane of microcapsules would, in theory, allow permeant metabolites to cross the membrane 1,250 times faster than in the standard 1 m2 area hemodialysis machine. If something can be placed inside these semipermeable microcapsules to trap entering metabolites then we have the basis for a miniaturized artificial organ based on artificial cells.