title: On-line sequential injection-capillary electrophoresis for near-real-time monitoring of extracellular lactate in cell culture flasks.
abstract: Cell culture has replaced many in vivo studies because of ethical and regulatory measures as well as the possibility of increased throughput. Analytical assays to determine (bio)chemical changes are often based on end-point measurements rather than on a series of sequential determinations. The purpose of this work is to develop an analytical system for monitoring cell culture based on sequential injection-capillary electrophoresis (SI-CE) with capacitively coupled contactless conductivity detection (C(4)D). The system was applied for monitoring lactate production, an important metabolic indicator, during mammalian cell culture. Using a background electrolyte consisting of 25mM tris(hydroxymethyl)aminomethane, 35mM cyclohexyl-2-aminoethanesulfonic acid with 0.02% poly(ethyleneimine) (PEI) at pH 8.65 and a multilayer polymer coated capillary, lactate could be resolved from other compounds present in media with relative standard deviations 0.07% for intraday electrophoretic mobility and an analysis time of less than 10min. Using the human embryonic kidney cell line HEK293, lactate concentrations in the cell culture medium were measured every 20min over 3 days, requiring only 8.73μL of sample per run. Combining simplicity, portability, automation, high sample throughput, low limits of detection, low sample consumption and the ability to up- and outscale, this new methodology represents a promising technique for near real-time monitoring of chemical changes in diverse cell culture applications.
authors.affiliation: Australian Center of Research on Separation Science, School of Pharmacy, Faculty of Health Sciences, University of Tasmania, Private Bag 26, Hobart, TAS 7001, Australia; Australian Center of Research on Separation Science, School of Chemistry, Faculty of Science, Engineering and Technology, University of Tasmania, Private Bag 75, Hobart, TAS 7001, Australia. Electronic address: Ala.Alhusban@utas.edu.au.
authors.forename: Ala A
authors.initials: AA
authors.lastname: Alhusban
authors.affiliation: Australian Center of Research on Separation Science, School of Chemistry, Faculty of Science, Engineering and Technology, University of Tasmania, Private Bag 75, Hobart, TAS 7001, Australia. Electronic address: Adam.Gaudry@utas.edu.au.
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Gaudry
authors.affiliation: Australian Center of Research on Separation Science, School of Chemistry, Faculty of Science, Engineering and Technology, University of Tasmania, Private Bag 75, Hobart, TAS 7001, Australia. Electronic address: mcb@utas.edu.au.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Breadmore
authors.affiliation: School of Pharmacy, Faculty of Health Sciences, University of Tasmania, Private Bag 26, Hobart, TAS 7001, Australia. Electronic address: Nuri.Guven@utas.edu.au.
authors.forename: Nuri
authors.initials: N
authors.lastname: Gueven
authors.affiliation: Australian Center of Research on Separation Science, School of Pharmacy, Faculty of Health Sciences, University of Tasmania, Private Bag 26, Hobart, TAS 7001, Australia. Electronic address: Rosanne.Guijt@utas.edu.au.
authors.forename: Rosanne M
authors.initials: RM
authors.lastname: Guijt
mesh_terms: D001331:Automation; D002448:Cell Adhesion; D018929:Cell Culture Techniques; D003470:Culture Media / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D057809:HEK293 Cells; D006801:Humans; D019344:Lactic Acid / Q000032:analysis* / Q000096:biosynthesis / Q000378:metabolism; D009862:Online Systems; D013997:Time Factors
chemical_list: D003470:Culture Media; D019344:Lactic Acid
keywords: Bio process monitoring; Capillary electrophoresis; Cell culture; Online monitoring; Sequential injection capillary electrophoresis