Continuous counter-current tangential chromatography (CCTC) where an adsorbent is suspended in a series of static mixers and recovered by hollow fibre membranes to allow the mobile phase to travel in the counter-current direction has been demonstrated to have advantages over traditional packed bed chromatography. Currently, chromatographic resin designed for packed bed operations is used as the adsorbent in CCTC systems. Not only is the resin affected by the feed and buffer composition, flow of the adsorbent slurry through the system can also negatively influence the lifetime and binding capacity by structurally damaging the material. This is particularly problematic as it can reduce the operational lifetime of the resin in a CCTC system.<br/><br/>An anion exchange polymethacrylate chromatographic resin was used to test the extent and types of damage CCTC can cause by the stirring and pumping involved in the process. Dynamic binding studies using BSA as a feed and particle size distributions were obtained after 9 cycles in a 200mL two-stage CCTC system and compared to a conventional packed bed system. The results show up to 35% loss in overall binding capacity, which is correlated with a 30% yield loss, while no significant change was detected in the column. The average bead size in the CCTC was shown to decrease from 71.5 to 62.7μm associated with the presence of fines ranging from 2.1 to 12.7μm. The origin of the fines was mainly due to the magnetic stirring in the hold tank to avoid slurry sedimentation.<br/><br/>The results demonstrate significant damage to the structural integrity of the bead shown by the finding of fines and reduction in particle size. Chromatographic adsorbents specifically designed to withstand the damaging forces resulting from slurry flow could be enabling for the further development of CCTC. Alternatively, CCTC equipment that damages the resin can be redesigned.

Understanding capacity loss during continuous counter-current tangential ion exchange chromatography

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.