title: Microfluidic differential immunocapture biochip for specific leukocyte counting.
abstract: Enumerating specific cell types from whole blood can be very useful for research and diagnostic purposes-e.g., for counting of CD4 and CD8 T cells in HIV/AIDS diagnostics. We have developed a biosensor based on a differential immunocapture technology to enumerate specific cells in 30 min using 10 μl of blood. This paper provides a comprehensive stepwise protocol to replicate our biosensor for CD4 and CD8 cell counts. The biochip can also be adapted to enumerate other specific cell types such as somatic cells or cells from tissue or liquid biopsies. Capture of other specific cells requires immobilization of their corresponding antibodies within the capture chamber. Therefore, this protocol is useful for research into areas surrounding immunocapture-based biosensor development. The biosensor production requires 24 h, a one-time cell capture optimization takes 6-9 h, and the final cell counting experiment in a laboratory environment requires 30 min to complete.
authors.affiliation: Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, William L. Everitt Laboratory, Urbana, Illinois, USA.|Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Biomedical Research Center, Carle Foundation Hospital, Urbana, Illinois, USA.
authors.forename: Umer
authors.initials: U
authors.lastname: Hassan
authors.affiliation: Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, William L. Everitt Laboratory, Urbana, Illinois, USA.
authors.forename: Nicholas N
authors.initials: NN
authors.lastname: Watkins
authors.affiliation: Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Biomedical Research Center, Carle Foundation Hospital, Urbana, Illinois, USA.
authors.forename: Bobby
authors.initials: B
authors.lastname: Reddy
authors.affiliation: Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Biomedical Research Center, Carle Foundation Hospital, Urbana, Illinois, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Damhorst
authors.affiliation: Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, William L. Everitt Laboratory, Urbana, Illinois, USA.|Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.|Biomedical Research Center, Carle Foundation Hospital, Urbana, Illinois, USA.
authors.forename: Rashid
authors.initials: R
authors.lastname: Bashir
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002452:Cell Count / Q000379:methods*; D006801:Humans; D007158:Immunologic Techniques / Q000379:methods*; D044085:Microfluidics / Q000379:methods*; D013997:Time Factors