Micro-tip chromatography; a route to an integrated strategy for high throughput bioprocess development.
Doctoral thesis, UCL (University College London).
Bioprocessing groups must keep pace with the many biologics and vaccines entering development, while ensuring process robustness, controlling costs, and accelerating project timelines. Microscale techniques provide a means to cope with these challenges by enabling high-throughput investigations to identify problems early, reduce requirements for costly large-scale experiments, and promote quality-bydesign approaches for process optimisation. Micro-tip columns (packed sorbent in a pipette tip) for chromatography and Adaptive Focused Acoustics (AFA) for cell disruption are two such techniques with potential to deliver high-throughput process development. This thesis characterises these platforms and integrates them as elements of the development workflow. Firstly, the key parameters are defined for robust, automated micro-tip chromatography. Finite-bath methods for isotherms and kinetic measurements are demonstrated, with sorbent contact time found to be critical for uptake of proteins on porous adsorbents, consistent with pore diffusion being rate-determining. Based upon these micro-tip data, two data-driven models are applied to predict dynamic binding capacity, one employing a shrinking-core model, and the other, a stagedreaction model. Both show satisfactory agreement with experimental laboratory column results. Micro-tip chromatography is then illustrated as an accelerated process development strategy for a mixed-mode chromatography step, with the results found to be predictive of laboratory column-scale yield, purity and capacity. In a second application, micro-tip chromatography is used to evaluate the interaction of upstream fermentation changes upon the downstream chromatography. The microscale chromatography is predictive of laboratory-scale yield and purity, despite being 1000-times smaller, while increasing productivity by over ten-fold. The miniaturisation of the chromatography, however, necessitates the development of a microscale cell disruption method to fully realise the gains in throughput and volume reduction. The AFA technique meets this goal, providing representative feed material for chromatographic study. Together, micro-tip chromatography and AFA form the basis for a next-generation bioprocess development platform.
|Title:||Micro-tip chromatography; a route to an integrated strategy for high throughput bioprocess development|
|Open access status:||An open access version is available from UCL Discovery|
|UCL classification:||UCL > School of BEAMS > Faculty of Engineering Science > Biochemical Engineering|
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