Thesis-PDF - IAP/TU Wien

apply recognition force microscopy to living cells (e.g. [55]). The ligandreceptor
binding is generally a reversible reaction. An advancement of above
technique led to the possibility of simultaneous identification of two types of
proteins in compositionally complex samples. ([56])
- Recognition imaging combines molecular recognition with surface imaging.
It means the mapping of ligand-receptor interaction sites on surfaces
with nanometer positional accuracy. E.g. identification and localization of
receptor binding sites distributed on biological membranes.
- Real Time Protein-Protein Interactions ([57])
Figure 3.7: The differentiation of atomic species by AFM as achieved
through measurement of short-range forces. Atoms of the same type are
colored the same. ([47])
3.3.2 Atomic Collection Information
- Surface topography
- Surface profiling
- Measurement of adhesion and friction of solid and liquid surfaces. This
can be achieved through measurement of lateral forces on the cantilever
tip. Any AFM that can measure the tilt (see Fig. 3.9) of its scanning
cantilever, e.g. with a four-quadrant photodiode, can perform lateral force
measurements. Lateral force microscopy (LFM) measures lateral deflections
(tilt) of the cantilever arising from forces on its tip parallel to the plane of
the sample surface. (ref. [58], [59], [60], [61], [62])
- Magnetic Force Microscopy (MFM). With an AFM cantilever, that is
coated with a ferromagnetic thin film, the spatial variation of magnetic forces
on a sample surface can be imaged. The tip is hovered over the surface in
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