Fluorescence anisotropy near-field scanning optical microscopy (FANSOM): a new technique for nanoscale microviscometry

Ultramicroscopy. 2002 Apr;90(4):259-64. doi: 10.1016/s0304-3991(01)00147-4.

Abstract

A near-field scanning optical microscope system was implemented and adapted for nanoscale steady-state fluorescence anisotropy measurement. The system as implemented can resolve approximately 0.1 cP microviscosity variations with a resolution of 250 nm laterally in the near field, or approximately 10 microm when employed in a vertical scanning mode. The system was initially used to investigate the extent of microviscous vicinal water over surfaces of varying hydrophilicity. Water above a cleaved mica surface was found to have a decreased microviscosity, while water above a hydrophobic surface showed no change (detection limit approximately 0.1 cP at approximately 30 + nm from the surface).

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Fluorescein
  • Fluorescence Polarization / instrumentation
  • Fluorescence Polarization / methods*
  • Fluorescent Dyes
  • Microscopy, Fluorescence / instrumentation
  • Microscopy, Fluorescence / methods*
  • Nanotechnology / methods*
  • Solutions
  • Viscosity
  • Water

Substances

  • Fluorescent Dyes
  • Solutions
  • Water
  • Fluorescein