(251a) Fractionation of Bsa and Lysozyme by Two-Sided Dead-End Electrofiltration

Downstream processing after a bioproduction is the bottle neck of this field of industry due to the high complexity of a bio suspension, the low concentration of the product and the stress sensitivity of the valuable target. A multitude of unit operations have to be stringed together to achieve an acceptable purity and concentration of the product each of which linked to a certain product loss. The trend in Downstream research is the combination of different separation techniques in one unit operation. In this work the combination of a dead-end membrane process is combined with an electrophoresis. The use of a two-sided dead-end mode made it possible to use two different membranes on the two sides of the filter chamber. This mode of operation led to a great enhancement in both filtration performance and selectivity. The separation of the two model proteins BSA and lysozyme could be performed at a pH level where the two substances are oppositely charged. Due to that the separation was according to both the electrophoretic mobility and the size differences. The finding is a promising result to have a technique that is more selective than state-of-the-art ultrafiltrations and faster than highly selective processes such as Gel-Electrophoresis or Chromatography.