Membrane-based affinity separation processes

Abstract

Affinity purification methods using solid matrices such as gels, crosslinked gels and silica beads have been well established for some time (Weetall, 1975; Scouten, 1981; Mosbach, 1988). For practical purposes, all the above-mentioned groups of matrices use columns and have restrictive flow rates and/or pressure requirements for their optimal applications. Due to recent advances in biotechnology, bioreactors of large capacities produce large volumes of recombinant biomolecules. Thus, a need has emerged for new affinity matrices (including ion exchangers) with faster flow rates, low back pressures and more economical systems. Such systems will pre-empt the need to use preparative methods such as the preconcentration of large volumes by ultrafiltration and/or chemical means before applying the sample on affinity columns. Preconcentration of large volumes of material is time-consuming, expensive and cumbersome. Faster methods, with the possibility of automation, are also needed for monitoring bioreactors and qualifying products, such as hybridoma cultures, before starting the separation processes.