Case study: The characterization and implementation of dielectric spectroscopy (biocapacitance) for process control in a commercial GMP CHO manufacturing process

Abstract

Dielectric spectroscopy (biocapacitance) is an up-and-coming technology for real time monitoring of biomass in cell culture processes and has opened the door for nextgeneration cell culture process control techniques such as automated on-demand nutrient feeding. In this case study we empirically demonstrate the lower limit of quantitation (LOQ), probe-to-probe consistency, and scalability of in situ biocapacitance probes using data generated from small-and large-scale Chinese hamster ovary (CHO) bioreactor cultures. The process understanding experiments culminated in the use of biocapacitance for process control in the current good manufacturing practices (GMP) manufacturing environment, first to automate the dilution of seed train cultures during scale-up stages and later as a method of predicting future glucose demand. The automated biomass-probe-based inoculation strategy yielded consistent results in six consecutive seed trains in the GMP manufacturing suite. In the process of improving our understanding of the technology we determined that biocapacitance could additionally be used as an indicator of a shift in the salt balance of a cell culture, and that collecting real time biomass data via biocapacitance has the potential to reduce the total timeline for feed strategy development by providing additional insights into culture performance which are not otherwise apparent using conventional optical cell counting methods.

Technology outlook for real‐time quality attribute and process parameter monitoring in biopharmaceutical development—A review

“…Viable cell density during the cell culture stage is an indication of overall “health” of the bioreactor, which in‐turn can be modulated to improve yields (Demuth, Poggendorf, Lüthi, Frank, & McNeel, 2016; Moore, Sanford, & Zhang, 2019). Capacitance‐based in‐situ probes for biomass concentration measurements have been widely employed across the industry for viable cell density monitoring (Demuth et al, 2016; Moore et al, 2019). The Hamilton Incyte® sensor is one of the industry‐leading capacitance technologies which can monitor viable cell density in real‐time.…”

Raman spectroscopic based chemometric models to support a dynamic capacitance based cell culture feeding strategy

“…The 15,000 L fed-batch bioreactors had a process duration of 13 days. Inoculation of the vessel was performed based on a calculation using a capacitance probe in the seeding vessel [28]. Dissolved oxygen was maintained to 40% by aeration and oxygen sparging while pH was controlled to a 7.00 pH set point with a deadband using carbon dioxide and base (sodium bicarbonate).…”

Elemental metal variance in cell culture raw materials for process risk profiling

“…Raw material sample preparation Biotechnology, Foster City, CA) with 2.5 L initial working volumes. 24 The work described herein used a CHO-K1 cell line with a fixed feed strategy, as opposed to the referenced biocapacitance-based feeding. For the method described herein, the procedures outlined in the U.S. Pharmacopeia General Chapter 233, 26 were roughly followed on a material by material basis.…”