Mechanical characterisation of agarose-based chromatography resins for biopharmaceutical manufacture

Abstract

Mechanical characterisation of agarose-based resins is an important factor in ensuring robust chromatographic performance in the manufacture of biopharmaceuticals. Pressure-flow profiles are most commonly used to characterise these properties. There are a number of drawbacks with this method, including the potential need for several re-packs to achieve the desired packing quality, the impact of wall effects on experimental set up and the quantities of chromatography media and buffers required. To address these issues, we have developed a dynamic mechanical analysis (DMA) technique that characterises the mechanical properties of resins based on the viscoelasticity of a 1ml sample of slurry. This technique was conducted on seven resins with varying degrees of mechanical robustness and the results were compared to pressure-flow test results on the same resins. Results show a strong correlation between the two techniques. The most mechanically robust resin (Capto Q) had a critical velocity 3.3 times higher than the weakest (Sepharose CL-4B), whilst the DMA technique showed Capto Q to have a slurry deformation rate 8.3 times lower than Sepharose CL-4B. To ascertain whether polymer structure is indicative of mechanical strength, scanning electron microscopy images were also used to study the structural properties of each resin. Results indicate that DMA can be used as a small volume, complementary technique for the mechanical characterisation of chromatography media.

Lifetime and Aging of Chromatography Resins during Biopharmaceutical Manufacture

“…However, there is a need to develop techniques that specifically monitor the mechanical deterioration of these resins over time or further still, establish a link between the observed structural decay and mechanical performance. There are a limited number of techniques at research scale that address this directly, such as work carried out by Nweke and colleagues [12] however, these techniques have yet to be employed for aging studies and the link to other performance parameters such as DBC is yet to be made.…”

Purification of Modified Therapeutic Proteins Available on the Market: An Analysis of Chromatography-Based Strategies

“…The purification of commercial PEGylated proteins is carried out mainly using agarose-based resins, followed by polymethacrylate-based resins ( Table 2 ). The mechanical strength of the resin is largely dependent on the material of the backbone matrix, particle size distribution, and particle porosity ( Nweke et al, 2017 ). Agarose and methacrylate-based matrices are often employed in ion exchangers for industrial scale purification of therapeutic proteins ( Pabst et al, 2007 ; Liu et al, 2010 ).…”

“…Agarose and methacrylate-based matrices are often employed in ion exchangers for industrial scale purification of therapeutic proteins ( Pabst et al, 2007 ; Liu et al, 2010 ). Agarose is commonly used as a backbone material because its manufacture and customization (i.e., porosity and functionalization) is relatively straightforward ( Nweke et al, 2017 ). Additionally, the high degree of hydroxylation of this natural polymer makes it highly hydrophilic, which prevents non-specific interactions with proteins ( Jungbauer, 2005 ).…”

Pressure drop in liquid chromatography

“…As there is no need to achieve critical velocity, proposed model can be applied on any chromatographic bed. Despite significance of a bed compression, there are only few studies investigating mechanical properties of chromatographic resins, probably because dedicated equipment allowing measurement on a micrometer scale or mechanical dynamic analysis should be implemented. These studies confirmed that there are differences in mechanical properties not only among different media but also within different functionalization chemistry of the same media.…”