A scale‐down mimic for mapping the process performance of centrifugation, depth and sterile filtration

Abstract

In the production of biopharmaceuticals disk‐stack centrifugation is widely used as a harvest step for the removal of cells and cellular debris. Depth filters followed by sterile filters are often then employed to remove residual solids remaining in the centrate. Process development of centrifugation is usually conducted at pilot‐scale so as to mimic the commercial scale equipment but this method requires large quantities of cell culture and significant levels of effort for successful characterization. A scale‐down approach based upon the use of a shear device and a bench‐top centrifuge has been extended in this work towards a preparative methodology that successfully predicts the performance of the continuous centrifuge and polishing filters. The use of this methodology allows the effects of cell culture conditions and large‐scale centrifugal process parameters on subsequent filtration performance to be assessed at an early stage of process development where material availability is limited. Biotechnol. Bioeng. 2016;113: 1934–1941. © 2016 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.

An automated laboratory‐scale methodology for the generation of sheared mammalian cell culture samples

“…The process performance of a given disk‐stack centrifuge can be altered through changes in bowl speed and flow rate. A previous study has shown that increases in bowl speed lead to higher levels of shear, as quantified through LDH release. In the present study (Fig.…”

“…This section summarizes the performance of the methodology developed to enable a range of EDRs relevant to the feed zone of disk‐stack centrifugation to be investigated in an automated and high throughput manner. A key advantage of using a FPLC instrument as a delivery system was that it enabled higher flow rates to be reached when compared to typical syringe pumps which were unable to maintain a set flow rate at high back pressures. Furthermore, the FPLC instrument had the utility of generating performance feedback through back pressure readings which enabled the calculation of EDRs (Eq.…”

“…Many studies have shown the exposure of mammalian cells to shear through flow constriction [8,9] or through the use of rheometers [10][11][12] can have a detrimental effect on cell viability. A number of devices described in the literature were shown to generate levels of shear comparable to those prevailing in the feed zone of typical disk-stack centrifuges [7,[13][14][15][16]. Most devices are based upon either the Rotating disk shear device (RSD) or the Capillary shear device (CSD).…”

“…The capillary shear device developed by Westoby et al , has also shown the ability to generate levels of shear similar to those of a disk‐stack centrifuge feed zone. Additionally, the combination of both devices (RSD and CSD) with a laboratory‐scale centrifuge have been shown to create centrates with comparable levels of solids remaining to those from a disk‐stack centrifuge . This publication develops an automated experimental methodology based upon the CSD capable of generating a range of shear levels typically produced in the feed zone of a disk‐stack centrifuge in addition to quantifying the back pressure enabling calculation of the EDRs.…”

Integrated process development ‐ quality by design compliant evaluation of upstream variations at the microscale level

“…This helps to understand the impact of upstream process development on the product and impurities and allows for a better estimation of the overall productivity . This is in line with quality by design (QbD) and process analytical technology (PAT) measures initiated by the regulators to better understand the manufacturing process and its impact on product quality attributes, which have increasingly become more important . In HTS, these demands are met by enabling multi‐parallel experimentation and automation of scale down methods accurately mimicking the process scale …”