Ultrafiltrates from 10 patients in chronic maintenance hemodialysis (7 males and 3 females) were obtained simultaneously using three different membranes: cuprophan, polyacrilonitrile and polysulfone. Middle molecules (MM) chromatographic profiles and total MM amount were determined by gel chromatography and high performance liquid chromatography.
The convective transport of MM was similar and not membrane related. Hemofiltration, a predominantly convective solute transfer procedure using high flux membranes such as polyacrilonitrile and polysulfone, in which large amounts of fluids have to be ultrafiltered, is an effective form of MM removal.
AsabaH., AlverstrandA., FürstP., Bergström: Clinical implications of uremic middle molecules in regular hemodialysis patients.Clin Nephrol1983; 19: 179–87.
6.
SchootsA.C., MikkersF.E., ClaessensH.A.Characterization of uremic “middle molecular” fractions by gas chronomatography, mass spectrometry, isotachophoresis and liquid chromatography.Clin Chem1982; 28: 45–9.
7.
ScribnerB.H.Discussion.Trans Am Soc Artif Intern Organs1965; 11: 29.
8.
ChapmanG.V., WardR.A., FarrellP.C.Separation and quantification of the “middle molecules” in uremia.Kidney Int1980; 17: 82–8.
