Axial Changes of Blood and Plasma Flow, Pressure, and Cellular Deposition in Capillary Plasma Filters

Abstract

The ability to separate plasma on-line from whole blood by membranes has generated interest in applying this process to source plasma collection and to the therapeutic treatment of various disease states. The availability of capillary membrane devices in particular has prompted investigations in these areas. The deposition of blood cellular elements has required the investigation of those parameters related to fluid and mass flux. Analytical solutions relating blood flow rate, filtration rate, and pressure and deposition with respect to axial distance have been obtained. Comparison of these solutions with preliminary experimental results have been made. Results indicate that the deposition parameter versus distance from the inlet is a very sensitive function of capillary membrane properties and operating conditions. Plasma fluxes are also highly dependent on blood, membrane, and filter properties and operating conditions.

Membrane Plasma Separation

“…The inverse relationship of cell radius has been noted to correlate in comparing bovine and dog blood; however, the correlation is not necessarily to the second power. The deposition parameter theory has been a useful guide to assess the axial changes in blood cell deposition (11) although the exact value of the parameter is variable and not reliable in design optimization.…”

A Local Model and Experimental Verification of the Crossflow Filtration of a Polydispersed Slurry

“…Considering the interaction forces between particles, Zydney [16] applied shear-induced diffusion in place of Brownian diffusion in concentration polarization theory to predict the filtration process of red blood cells and found that the prediction results were in good agreement with the experimental values. In addition, assuming a balance between inertial lift and hydrodynamic force in equilibrium, some researchers [17][18][19] proposed models that apply inertial lift instead of particle diffusion. According to experimental verification, the inertial lift theory is generally applied to solid particles larger than 30 µm [20].…”