Imaging of DNA molecules by scanning near-field microscope

Citation
H. Muramatsu et al., Imaging of DNA molecules by scanning near-field microscope, MAT SCI E C, 12(1-2), 2000, pp. 29-32
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
MATERIALS SCIENCE & ENGINEERING C-BIOMIMETIC AND SUPRAMOLECULAR SYSTEMS
ISSN journal
0928-4931 → ACNP
Volume
12
Issue
1-2
Year of publication
2000
Pages
29 - 32
Database
ISI
SICI code
0928-4931(20000818)12:1-2<29:IODMBS>2.0.ZU;2-H
Abstract
We utilized a novel scanning near-field optical microscope (SNOM) for imagi ng DNA molecules. The microscope system was constructed with a commercial i nverse microscope and a newly developed scanning unit. In the system, a ben t optical fiber probe is used to operate in a dynamic mode atomic-force mic roscope (AFM). A lambda DNA solution of 5 mu M (base) with 5 mu M and 500 n M YOYO-1 was prepared and cast on a gamma-APTES treated cover slip. The lam bda DNA was aggregated in line and immobilized on the cover slip. The perce ntage of fluorescence intensity of lambda DNA with 5 mu M YOYO-1 showed int egers at almost each point on the DNA. As the fluorescence intensity correl ated with the areas of a cross-section of the DNA topography, it appeared t hat YOYO-1 intercalated in the DNA homogeneously. The fluorescence images o f lambda DNA with 500 mu M YOYO-1, however, were irregular and did not corr elate with the area of the topographic cross-section, suggesting that YOYO- 1 did not intercalate in the lambda DNA uniformly in this concentration and intercalated cooperatively. (C) 2000 Elsevier Science S.A. All rights rese rved.