A near-infrared fluorescent voltage-sensitive dye allows for moderate-throughput electrophysiological analyses of human induced pluripotent stem cell-derived cardiomyocytes

Am J Physiol Heart Circ Physiol. 2014 Nov 1;307(9):H1370-7. doi: 10.1152/ajpheart.00344.2014. Epub 2014 Aug 29.


Human induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM)-based assays are emerging as a promising tool for the in vitro preclinical screening of QT interval-prolonging side effects of drugs in development. A major impediment to the widespread use of human iPSC-CM assays is the low throughput of the currently available electrophysiological tools. To test the precision and applicability of the near-infrared fluorescent voltage-sensitive dye 1-(4-sulfanatobutyl)-4-{β[2-(di-n-butylamino)-6-naphthyl]butadienyl}quinolinium betaine (di-4-ANBDQBS) for moderate-throughput electrophysiological analyses, we compared simultaneous transmembrane voltage and optical action potential (AP) recordings in human iPSC-CM loaded with di-4-ANBDQBS. Optical AP recordings tracked transmembrane voltage with high precision, generating nearly identical values for AP duration (AP durations at 10%, 50%, and 90% repolarization). Human iPSC-CMs tolerated repeated laser exposure, with stable optical AP parameters recorded over a 30-min study period. Optical AP recordings appropriately tracked changes in repolarization induced by pharmacological manipulation. Finally, di-4-ANBDQBS allowed for moderate-throughput analyses, increasing throughput >10-fold over the traditional patch-clamp technique. We conclude that the voltage-sensitive dye di-4-ANBDQBS allows for high-precision optical AP measurements that markedly increase the throughput for electrophysiological characterization of human iPSC-CMs.

Keywords: QT prolongation; acquired long QT syndrome; optical action potential; preclinical drug screening; stem cell model.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • 2-Naphthylamine / analogs & derivatives*
  • 2-Naphthylamine / chemistry
  • Action Potentials*
  • Cell Differentiation
  • Fluorescent Dyes*
  • Humans
  • Induced Pluripotent Stem Cells / cytology
  • Induced Pluripotent Stem Cells / physiology*
  • Infrared Rays
  • Myocytes, Cardiac / cytology
  • Myocytes, Cardiac / physiology*
  • Quinolinium Compounds / chemistry*
  • Voltage-Sensitive Dye Imaging / methods*


  • 1-(4-sulfanatobutyl)-4-(beta-(2-(di-n-butylamino)-6-naphthyl)butadienyl)quinolinium betaine
  • Fluorescent Dyes
  • Quinolinium Compounds
  • 2-Naphthylamine