W. Wiegrabe et al., SCANNING NEAR-FIELD OPTICAL MICROSCOPE - A METHOD FOR INVESTIGATING CHROMOSOMES, Surface and interface analysis, 25(7-8), 1997, pp. 510
Karyotypes of human metaphase chromosomes are used to detect genetic d
efects like deletions or translocations. For these investigations the
chromosomes are treated by the trypsin-Giemsa protocol, resulting in a
typical banding pattern. These patterns are investigated using conven
tional light microscopy. Because of the diffraction limit, even the sm
allest visible band contains similar to 1 million base pairs. We want
to improve resolution by using bright-field scanning near-field optica
l microscopy (SNOM). Images of trypsin-Giemsa-treated chromosomes are
presented and compared with conventional light microscopic, scanning f
orce and scanning fluorescence near-field optical microscopic data. Fo
r fluorescence investigations, the chromosomes were stained using prop
idium iodide. To our knowledge, it is the first attempt to investigate
G-banded chromosomes by SNOM. (C) 1997 by John Wiley & Sons, Ltd.