Biomedical Microdevices

, Volume 15, Issue 2, pp 255–259 | Cite as

hERG drug response measured in droplet bilayers

  • Shiva A. Portonovo
  • Carl S. Salazar
  • Jacob J. Schmidt
Article

Abstract

We show measurements of the human cardiac potassium ion channel Kv11.1 (hERG) in droplet bilayers incorporated directly from commercial membrane preparations of HEK293 cells. Although we do not obtain ensemble conductance kinetics and rectification observed in patch clamp measurements of hERG, ensemble currents measured in our system showed inhibition dependent on astemizole and E-4031 concentration, with IC50 values similar to those found with patch clamp. The availability of engineered HEK cells expressing a variety of ion channels, combined with the simplicity of the inhibition measurement, suggest that droplet bilayers may have considerable technological potential for determination of ion channel drug potency.

Keywords

Ion channel Inhibition hERG Lipid bilayer Screening 

Supplementary material

10544_2012_9725_MOESM1_ESM.docx (15.1 mb)
ESM 1(DOCX 15501 kb)

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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Shiva A. Portonovo
    • 1
  • Carl S. Salazar
    • 1
  • Jacob J. Schmidt
    • 1
  1. 1.Department of BioengineeringUniversity of California, Los AngelesLos AngelesUSA

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