Regensburg 2016 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
BP: Fachverband Biologische Physik
BP 11: Bioimaging and Spectroscopy II
BP 11.6: Talk
Monday, March 7, 2016, 16:45–17:00, H43
Non-contact atomic force microscopy of the purple membrane — •Alfred J. Weymouth1, Katharina Pfeffer1, Estefania Mulvihill2, Daniel J. Müller2, and Franz J. Giessibl1 — 1Department of Physics, University of Regensburg, Regensburg, Germany — 2Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
Atomic force microscopy is a unique tool for investigating biological samples. Images are normally acquired in tapping mode, in which the tip presses down on the sample with each oscillation. This is relatively non-destructive, requires only a small sample, and can resolve down to the nanometer-scale. (e.g. [1]) However, true non-contact techniques, such as frequency-modulation AFM, have been developed which allow atomic resolution before the tip presses down on the surface. Frequency-modulation AFM has acquired atomic contrast on surfaces in liquid environments. [2] We have started to explore the possibility of using non-contact AFM with a stiff cantilever (a qPlus sensor with k = 3515 N/m) to image biological membranes. As a first sample, we looked at the purple membrane. We present our first results of the membrane islands and atomic resolution of the mica substrate.
[1] M. Pfreundschuh, D. Martinez-Martin, E. Mulvihill, S. Wegmann and D.J. Müller. Nat Protoc, 9, 1113 (2014)
[2] T. Fukuma, K. Kobayashi, K. Matsushige and H. Yamada. Appl Phys Lett, 87, 034101 (2005)