Sensitivity of second harmonic generation from styryl dyes to transmembrane potential

Biophys J. 2004 Feb;86(2):1169-76. doi: 10.1016/S0006-3495(04)74191-0.

Abstract

In this article we present results from the simultaneous nonlinear (second harmonic generation and two-photon excitation fluorescence) imaging and voltage clamping of living cells. Specifically, we determine the sensitivity to transmembrane potential of second harmonic generation by ANEP-chromophore styryl dyes as a function of excitation wavelength and dye structure. We have measured second harmonic sensitivities of up to 43% per 100 mV, more than a factor of four better than the nominal voltage sensitivity of the dyes under "one-photon" fluorescence. We find a dependence of voltage sensitivity on excitation wavelength that is consistent with a two-photon resonance, and there is a significant dependence of voltage sensitivity on the structure of the nonchromophore portion of the dyes.

Publication types

  • Evaluation Study
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cinnamates / metabolism
  • Fluorescent Dyes
  • Lasers
  • Membrane Potentials*
  • Mice
  • Microscopy, Confocal / methods*
  • Microscopy, Fluorescence / methods*
  • Neuroblastoma / pathology*
  • Neuroblastoma / physiopathology*
  • Nonlinear Dynamics
  • Patch-Clamp Techniques / methods*
  • Pyridinium Compounds*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Staining and Labeling / methods*

Substances

  • Cinnamates
  • Fluorescent Dyes
  • Pyridinium Compounds
  • cinnamic acid
  • 1-(3-sulfonatopropyl)-4-(beta)(2-(di-n-butylamino)-6-naphthylvinyl)pyridinium betaine