High-resolution protein separation using a laterally-fed membrane chromatography device

Radial-flow membrane chromatography devices which are used for flow-through separation are generally unsuitable for bind-and-elute chromatography, particularly where multiple components need to be separated. We discuss a laterally-fed membrane chromatography device, suitable for high-resolution, multi-component protein separation in the bind-and-elute mode. In the current study, a stack of cation exchange membranes was housed within the membrane device and its performance was compared with an equivalent commercial radial-flow device having the same membrane bed volume and bed height. Tracer experiments were carried out using sodium chloride solution to compare their residence time distributions. The laterally-fed device showed superior flow distribution characteristics, which could be attributed to a lower variability in solute-flow path-lengths, and a smaller dead volume. Single protein bind-and-elute experiments carried out using lysozyme showed that the peaks obtained with the laterally-fed device were significantly sharper and more symmetrical. Excellent separation of three model proteins ovalbumin, conalbumin and lysozyme demonstrated that the laterally-fed membrane chromatography device was indeed suitable for carrying out high-resolution multi-component protein purification. These proteins could be fractionated in about 10 membrane bed volumes using the laterally-fed device as opposed to 25 bed volumes with the radial-flow device. The design of the laterally-fed device is simple and its flat shape gives it significantly lower footprint and offers additional advantages such as stackability and ease of multiplexing.