Atomic Force Microscopy of Isolated Nanostructures: Biomolecular Imaging in Hydrated Environments – Status and Future Prospects

  • Sergio Santos
  • Neil H. Thomson
Part of the NanoScience and Technology book series (NANO)


The use of the atomic force microscope (AFM) in ambient conditions has some key advantages for characterising isolated nanostructures over other operating environments. The lack of a bulk liquid environment minimises motion of the sample to maximise resolution, while humidity control allows retention of surface water, keeping biomolecules sufficiently hydrated. The use of relatively stiff cantilevers in air (k > 10 N/m) prevents significant energy being transferred to higher modes or frequencies. This enables reliable modelling of the cantilever dynamics with relatively straightforward point mass and spring models. We show herein that combining modelling with experiment leads to robust interpretation of dynamic AFM in air. This understanding has led to new ways of operation, including a true non-contact mode in ambient and small amplitude small set-point (SASS) modes. These modes will be important to gain quantitative information about structure and processes on the nanoscale. We also discuss interpretation of height information obtained from AFM on the nanoscale and summarise a framework for recovery of apparent height loss for nanostructures. A combination of these methods will lead to a new era of quantitative AFM for nanoscience and nanotechnology.


Atomic Force Microscope Amplitude Modulation Scanning Tunnelling Microscope Atomic Force Microscope Technique Force Regime 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We would like to acknowledge Matteo Chiesa and Marco Stefancich (Masdar Institute of Science and Technology) for their comments when developing this work and Maritsa Kissamitaki for helping with the artwork. We would also like to thank Dr. David Adams, Dr. Simon Connell and Dr. Toby Kurk for their contribution to this work (Oscillatoria A2 cyanobacterium, Fig. 5.12).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Sergio Santos
    • 1
  • Neil H. Thomson
    • 1
  1. 1.Molecular and Nanoscale Physics Group, School of Physics and AstronomyUniversity of LeedsLeedsUK

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