{814} revision 4 modified: 01-15-2012 23:00 gmt

PMID-19199762[0] Optical Detection of Brain Cell Activity Using Plasmonic Gold Nanoparticles

  • Used 140 nm diameter, 40 nm thick gold disc nanoparticles set in a 400nm array, illuminated by 850nm diode laser light.
    • From my reading, it seems that the diameter of these nanoparticles is important, but the grid spacing is not.
  • These nanoparticles strongly scatter light, and the degree of scattering is dependent on the local index of refraction + electric field.
  • The change in scattering due to applied electric field is very small, though - ~ 3e-6 1/V in the air-capacitor setup, ~1e-3 in solution when stimluated by cultured hippocampal neurons.
  • Noteably, nanoparticles are not diffraction limited - their measurement resolution is proportional to their size. Compare with voltage-sensitive dyes, which have a similar measurement signal-to-noise ratio, are diffraction limited, may be toxic, and may photobleach.


[0] Zhang J, Atay T, Nurmikko AV, Optical detection of brain cell activity using plasmonic gold nanoparticles.Nano Lett 9:2, 519-24 (2009 Feb)