Open AccessEffect of Membrane Characteristics on the Performance of Couette Rotating Plasma Separation Devices
Author(s) -
Michel Y. Jaffrin,
G. Beaudoin,
Luhui Ding,
N. Djennaoui
Publication year - 1989
Publication title -
asaio transactions
Language(s) - English
Resource type - Journals
eISSN - 2375-0952
pISSN - 0889-7190
DOI - 10.1097/00002480-198907000-00169
Subject(s) - plasma , separation (statistics) , membrane , materials science , chemistry , chromatography , physics , computer science , biochemistry , nuclear physics , machine learning
The concept of a cylindrical membrane rotating at high speed inside a concentric cylinder (Couette flow device) has proved to be very efficient for plasma separation from whole blood. The authors show that its high filtration velocity (about 0.5-0.6 cm/min) is due to the presence of Taylor vortices in the blood-filled annular gap, which greatly increase the shear rates, but not radial migration of formed elements under centrifugal forces. The variation of filtrate velocity with transmembrane pressure (ptm) markedly depends upon the type of membrane. With a 0.8 micron polycarbonate membrane and bovine blood at 40% hematocrit, the filtration velocity reaches a peak equal to 0.6 cm/min at 3,000 rpm, then decreases to 80 mmHg, reaching a plateau of 0.35 cm/min independent of ptm. With a nylon membrane of 0.5 micron pores under the same conditions, the filtration velocity does not present a peak, but rises continuously to reach a 90 mmHg plateau equal to 0.5 cm/min. Similar behavior, but with lower plateaus, is also obtained with polycarbonate membranes at pore sizes below 0.4 microns. At 3,000 rpm, hemolysis occurs if ptm exceeds 750 mmHg, far above the operating range.