Atomic-force microscopy (AFM) is based on the detection of local forces acting between a sharp tip and the sample. The tip scans the sample and differences in height are registered. A surface profile of the sample is generated with a resolution that can be orders of magnitude better than the one yielded by light microscopy. Piezoelectric elements accurately control the precise movements of the tip. The atomic force microscope at the IMIT is mounted on an inverted optical microscope allowing for simultaneous fluorescence and AFM imaging.
JPK Instruments NanoWizzard III
Key features:
mounted on an Olympus inverted fluorescence microscope
Direct Overlay feature for combination of AFM and optical microscopy
100x100x15 µm scan range
contact and lateral force and advanced AC modes like non-contact and phase detection
Research example
Surface topology of Streptomyces spores
Günther Muth1 and Filipp Oesterhelt2 Departments of Microbiology / Biotechnology1 and Microbial Bioactive Compounds2
Cover glasses with spore chains of Streptomyces sp. were imaged via an inverted optical microscope to select for hyphae at the specific stage of sporulation. The area of interest for AFM imaging was selected directly in an image of the spore chain taken by the CCD camera, using the "direct overlay" option provided in the AFM software.