Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Oct;118(10):3888-3897.
doi: 10.1002/bit.27865. Epub 2021 Jun 23.

Investigating trace metal precipitation in highly concentrated cell culture media with Pourbaix diagrams

Timothy Brantley  1 , Brandon Moore  1 , Chris Grinnell  2 , Sarwat Khattak  1
Affiliations

Investigating trace metal precipitation in highly concentrated cell culture media with Pourbaix diagrams

Timothy Brantley et al. Biotechnol Bioeng. 2021 Oct.

Abstract

Commercial production of therapeutic proteins using mammalian cells requires complex process solutions, and consistency of these process solutions is critical to maintaining product titer and quality between batches. Inconsistencies between process solutions prepared at bench and commercial scale may be due to differences in mixing time, temperature, and pH which can lead to precipitation and subsequent removal via filtration of critical solution components such as trace metals. Pourbaix diagrams provide a useful tool to model the solubility of trace metals and were applied to troubleshoot the scale-up of nutrient feed preparation after inconsistencies in product titer were observed between bench- and manufacturing-scale batches. Pourbaix diagrams modeled the solubility of key metals in solution at various stages of the nutrient feed preparation and identified copper precipitation as the likely root cause of inconsistent medium stability at commercial scale. Copper precipitation increased proportionally with temperature in bench-scale preparations of nutrient feed and temperature was identified as the root cause of copper precipitation at the commercial scale. Additionally, cell culture copper titration studies performed in bench-scale bioreactors linked copper-deficient mammalian cell culture to inconsistent titers at the commercial scale. Pourbaix diagrams can predict when trace metals are at risk of precipitating and can be used to mitigate risk during the scale-up of complex medium preparations.

Keywords: CHO; Pourbaix diagram; basic isoform; copper; media precipitation; product quality.

PubMed Disclaimer

References

REFERENCES

    1. Beck, A., & Liu, H. (2019). Macro- and micro-heterogeneity of natural and recombinant IgG antibodies. Antibodies (Basel), 8(1), 18. https://doi.org/10.3390/antib8010018
    1. Boulet, A., Vest, K. E., Maynard, M. K., Gammon, M. G., Russell, A. C., Mathews, A. T., & Cobine, P. A. (2018). The mammalian phosphate carrier SLC25A3 is a mitochondrial copper transporter required for cytochrome c oxidase biogenesis. Journal of Biological Chemistry, 293(6), 1887-1896. https://doi.org/10.1074/jbc.RA117.000265
    1. Bruhlmann, D., Jordan, M., Hemberger, J., Sauer, M., Stettler, M., & Broly, H. (2015). Tailoring recombinant protein quality by rational media design. Biotechnology Progress, 31(3), 615-629. https://doi.org/10.1002/btpr.2089
    1. Cao, X., Loussaert, J. A., & Wen, Z. Q. (2016). Microspectroscopic investigation of the membrane clogging during the sterile filtration of the growth media for mammalian cell culture. Journal of Pharmaceutical and Biomedical Analysis, 119, 10-15. https://doi.org/10.1016/j.jpba.2015.11.014
    1. de Chialvo, M. R. G., Marchiano, S. L., & Arvía, A. J. (1984). The mechanism of oxidation of copper in alkaline solutions. Journal of Applied Electrochemistry, 14(2), 165-175. https://doi.org/10.1007/bf00618735

LinkOut - more resources