Abstract
According to the improvement of hemodialysis membrane limitation of solute permeability, the dialyzer is able to eliminate low molecular weight proteins not only by convection, but also by diffusion. The permeation of low molecular weight proteins means diffusion of same molecular weight materials from dialysate to the blood compartment when these exist in the dialysate. Blood contamination with antigen proteins will cause various immunoreactions, which may lead to unknown uremic complications. Therefore, to eliminate these proteins in the dialysate line between the dialysis machine and the dialyzer, adsorptive removal with ceramic powder was devised. The diameter of this ceramic powder is from 100 to 200um and average pore diameter is 1, 500Å. Batchwise operation which had 1g of ceramic powder and 100ml solution of a marker protein in acetic acid dialysate showed the decrease of concentration. The order of adsorption capacity is as follows; lysozyme, cytochrome C, ribonuclease A and α-lactalbumin. It is same as the descending order of isoelectric point. Another experiment with a column of 10mm diameter, containing 1g ceramic powder, showed the elimination of 1, 000ng/ml lysozyme in dialysate which flowed into the column as single pass. The removal ratio is around 80% at from 3 to 11 sec residence time. This result shows the rapid adsorption of protein onto the ceramic surface. Low isoelectric point proteins are not so well adsorped as high isoelectric point proteins, the modification of the ceramic powder, such as pore radius variation and/or surface reactant modulation, makes an effective removal of all kinds of proteins and toxic substances which will exist in dialysate.
