title: On-chip non-invasive and label-free cell discrimination by impedance spectroscopy.
abstract: OBJECTIVE
  Many flow-cytometric cell characterization methods require costly markers and colour reagents. We present here a novel device for cell discrimination based on impedance measurement of electrical cell properties in a microfluidic chip, without the need of extensive sample preparation steps and the requirement of labelling dyes.
  
  
  RESULTS
  We demonstrate that in-flow single cell measurements in our microchip allow for discrimination of various cell line types, such as undifferentiated mouse fibroblasts 3T3-L1 and adipocytes on the one hand, or human monocytes and in vitro differentiated dendritic cells and macrophages on the other hand. In addition, viability and apoptosis analyses were carried out successfully for Jurkat cell models. Studies on several species, including bacteria or fungi, demonstrate not only the capability to enumerate these cells, but also show that even other microbiological life cycle phases can be visualized.
  
  
  CONCLUSIONS
  These results underline the potential of impedance spectroscopy flow cytometry as a valuable complement to other known cytometers and cell detection systems.
authors.affiliation: Leister Process Technologies, Axetris Microsystems Division, Kägiswil, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Schade-Kampmann
authors.forename: A
authors.initials: A
authors.lastname: Huwiler
authors.forename: M
authors.initials: M
authors.lastname: Hebeisen
authors.forename: T
authors.initials: T
authors.lastname: Hessler
authors.forename: M
authors.initials: M
authors.lastname: Di Berardino
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D003513:Cycloheximide / Q000494:pharmacology; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects; D017097:Electric Impedance; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D006801:Humans; D019169:Jurkat Cells; D051379:Mice; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D009000:Monocytes / Q000166:cytology / Q000187:drug effects; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000187:drug effects; D013057:Spectrum Analysis / Q000295:instrumentation*; D013194:Staining and Labeling; D013997:Time Factors
chemical_list: D003513:Cycloheximide