Format

Send to

Choose Destination
See comment in PubMed Commons below
Rev Sci Instrum. 2013 Oct;84(10):103709. doi: 10.1063/1.4826494.

Operation of astigmatic-detection atomic force microscopy in liquid environments.

Author information

1
Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan.

Abstract

The astigmatic detection system (ADS) based on commercial optical pickup head was demonstrated to achieve a sub-nanometer sensitivity in detecting the vertical movement of an object surface in air. The detection laser spot of the ADS was sub-μm and the detection bandwidth was over 80 MHz. These advantages allow detection of high-frequency mechanical resonance of very small objects, which would have many important applications in nanotechnology. In this work, we optimized the operation conditions of ADS to achieve good sensitivity in aqueous solutions. We demonstrated good contrast and good spatial resolution of cancer cells in water with the optical profilometry mode. We also built an ADS-AFM (atomic force microscopy) for imaging in water. A novel cantilever holder was designed, and the spurious peaks were suppressed down to 26.0% of the real resonance peak. Most importantly, we demonstrated that the ADS-AFM could resolve single atomic steps on a graphite substrate and image soft DNA molecules on mica in water.

PMID:
24182121
DOI:
10.1063/1.4826494
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for American Institute of Physics
    Loading ...
    Support Center