Rd. Schaller et al., Near-field second harmonic imaging of granular membrane structures in natural killer cells, J PHYS CH B, 104(22), 2000, pp. 5217-5220
Second Harmonic Generation (SHG) has been used in combination with a near-f
ield scanning optical microscope (NSOM) to image biological samples for the
first time. Near-field SHG images of azure B stained mouse natural killer
(NK) cells were recorded at four different wavelengths using a tunable near
-infrared femtosecond laser. The surface specificity of SHG allows membrane
structures to be selectively imaged with subdiffraction spatial resolution
under ambient conditions. Resonance enhancement of SHG is shown to provide
a chemically specific contrast mechanism in NSOM imaging, revealing submic
ron features associated with the cytolytic granular membrane.