beta 2-Microglobulin and other low molecular weight proteins in haemodiafiltrates and in haemofiltrates

Uraemic patients underwent haemodialysis by cuprophan membrane, or haemodiafiltration by polyacrylonitrile membrane, or haemofiltration by acetate cellulose membrane. Plasma samples drawn before and after treatment with the dialyser were gel-filtered on Sephadex G-75. A comparison of the chromatograms showed that the treatment causes a removal of middle molecules, which is more consistent when haemodiafiltration and haemofiltration are used. Protein removal was examined in the fluids from the three dialysers. It was observed that proteins (300 +/- 45 mg and 410 +/- 60 mg respectively) were removed when polyacrylonitrile and acetate cellulose membranes were used, but not in the case of cuprophan membrane. beta 2-Microglobulin was the protein lost in the greatest amount.