Details

Autor(en) / Beteiligte

• Mikamo-Satoh, Eriko
• Yamada, Fumihiko
• Takagi, Akihiko
• Matsumoto, Takuya
• Kawai, Tomoji

Titel

Electrostatic force microscopy: imaging DNA and protein polarizations one by one

Ist Teil von

• Nanotechnology, 2009-04, Vol.20 (14), p.145102-145102

Ort / Verlag

England

Erscheinungsjahr

2009

Quelle

MEDLINE

Beschreibungen/Notizen

• We present electrostatic force microscopy images of double-stranded DNA and transcription complex on an insulating mica substrate obtained with molecular resolution using a frequency-mode noncontact atomic force microscope. The electrostatic potential images show that both DNA and transcription complexes are polarized with an upward dipole moment. Potential differences of these molecules from the mica substrate enabled us to estimate dipole moments of isolated DNA and transcription complex in zero external field to be 0.027 D/base and 0.16 D/molecule, respectively. Scanning capacitance microscopy demonstrates characteristic contrast inversion between DNA and transcription complex images, indicating the difference in electric polarizability of these molecules. These findings indicate that the electrostatic properties of individual biological molecules can be imaged on an insulator substrate while retaining complex formation.