A MECHANISTIC MODEL OF PLASMA FILTRATION

A model describing the sieving and transmembrane pressure behavior of plasma filtration is developed and numerically simulated. The model as sumes a mechanistic criteria for particle passage through a membrane w ith cylindrical pores. The initial pore diameter distribution and poro sity are assumed to be known. Model inputs include the particle diamet er distribution, concentration and total flow rate of the permeate pla sma solution. Outputs of the model include transmembrane pressure, the time-averaged sieving coefficients, and size distributions of the dep osited particles and accumulated filtrate particles. Optimal filtratio n is characterized by high, stable sieving coefficients for desired pa rticles, high retention of larger particles and relatively small incre ases in transmembrane pressure. These characteristics are realized for membranes with mean pore diameters equal to or slightly larger than m ean permeate particle diameters. Simulations demonstrate that the inco rporation of membrane properties into models of plasma filtration is b oth significant and readily possible. (C) 1998 IPEM. Published by Else vier Science Ltd. All rights reserved.