Fluorescence axial localization with nanometer accuracy and precision.
We describe a new technique, standing wave axial nanometry (SWAN), to image the axial location of a single nanoscale fluorescent object with sub-nanometer accuracy and 3.7 nm precision. A standing wave, generated by positioning an atomic force microscope tip over a focused laser beam, is used to excite fluorescence; axial position is determined from the phase of the emission intensity. We use SWAN to measure the orientation of single DNA molecules of different lengths, grafted on surfaces with different functionalities.
Department of Physics and Astronomy, Iowa State University, Iowa, USA.
Hui
H
Li
Chi-Fu
CF
Yen
Sanjeevi
S
Sivasankar
D004247:DNA / Q000737:chemistry*; D005453:Fluorescence; D018625:Microscopy, Atomic Force; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D009690:Nucleic Acid Conformation; D013499:Surface Properties
D004247:DNA