Abstract:
:Cost-effective production of biopharmaceuticals on a large scale can be carried out by perfusion cultures of mammalian cells. One problem with this mode of operation for submerged free-cell cultures is the requirement for an efficient cell separation device located in the effluent stream. The present work investigates the potential for the development of a novel dielectrophoresis-based cell separator, capable of providing selective retention of viable cells in cell culture media, which are highly conductive. Predictions of the dielectrophoretic (DEP) response in culture media were first obtained through a series of DEP-levitation experiments. Subsequently, a prototype microelectrode "filter" was microfabricated and tested with C174 myeloma cell suspensions of density 1 x 10(6) cells/mL. The optimum frequency range for selective retention of viable cells was found in the range 5-15 MHz. A maximum separation efficiency of 98% was achieved at 10 MHz, with an applied peak-to-peak voltage of 30 V (maximum field strength of 10(5) V/m) and a flow rate of 30 mL/h which corresponds to a superficial velocity of 5.23 cm/h through the DEP-filter channels.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Docoslis A,Kalogerakis N,Behie LA,Kaler KVdoi
10.1002/(SICI)1097-0290(19970505)54:3<239::AID-BITsubject
Has Abstractpub_date
1997-05-05 00:00:00pages
239-50issue
3eissn
0006-3592issn
1097-0290journal_volume
54pub_type
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