Abstract:
:Dielectric spectroscopy was applied to two industrial high cell density culture processes and used to determine on-line the concentration of CHO cells immobilized on macroporous microcarriers in a stirred bioreactor and in a packed-bed of disk carriers. The cell concentration predicted from the spectroscopic data was in excellent agreement with off-line cell counting data for both processes. Deviations between the two counting methods only occurred in the case of a significant decrease of the cell viability, from 93% to 64%, which induced a change of the average cell size in the culture. Results for the packed-bed process were further confirmed by the application of indirect yield models based on the measurement of glucose, lactate, and the protein of interest. Moreover, dielectric spectroscopy was used as a tool to characterize the packed-bed process. It was possible to determine both the maximum cell concentration that could be reached in the culture system, 2.0 x 10(11) cell per kg of disk carrier, and to quantify the increase of specific protein productivity induced by the production phase, from 5.14 x 10(-8) microg x cell(-1) x h(-1) to 4.24 x 10(-7) microg x cell(-1) x h(-1).
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Ducommun P,Kadouri A,von Stockar U,Marison IWdoi
10.1002/bit.1197subject
Has Abstractpub_date
2002-02-05 00:00:00pages
316-23issue
3eissn
0006-3592issn
1097-0290pii
10.1002/bit.1197journal_volume
77pub_type
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journal_title:Biotechnology and bioengineering
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pub_type: 杂志文章
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journal_title:Biotechnology and bioengineering
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