US-Turkey Cooperative Research: A New High Resolution AFM Technique for Biological Imaging

Wayne State University, Detroit MI

Investigators

Abstract

0217789 Hoffmann Description: This award is for support of a joint research project between Dr. Peter Hoffmann, Department of Physics and Astronomy, Wayne State University, Detroit, Michigan and Dr. Ahmet Oral, Physics Department, Bilkent University, Ankara, Turkey. They plan to study the development of a new high-resolution Atomic Force Microscopy (AFM) technique for biological imaging. Commonly used AFM techniques face fundamental limits to further improvement. These limitations are due to fundamental operating principles of common AFM techniques, which cannot be changed by simple adjustments of parameters. The PIs plan to design and build a prototype of an AFM technique that avoids these limitations and, in principle, should be able to provide non-contact atomic resolution imaging and direct quantitative point-by-point measurements of interactions in situ in liquids. This AFM technique relies on a sub-resonance, ultra-small (< 1A) oscillation of the AFM cantilever. This linearizes the measurement and makes data interpretation straightforward. Scope: This award will allow a US scientist to collaborate with a Turkish scientist in a research project of high scientific potential. The nanomechanics of biomolecules and the direct imaging of biological structures are of great interest in biochemistry, bioengineering and medicine. The two scientists were directly involved in the development of an ultra-high vacuum (UHV) and a preliminary liquid-based version of the above described AFM technique which proved to be successful in UHV and in liquid. However, the liquid based AFM was very difficult to use and had some fundamental design issues, which will be addressed in this collaboration. The ultimate goal would be the construction of a user-friendly new AFM technique based on a novel operational principle, and the imaging and measurement of actual biological structures. The development of this instrument would enhance current work by the PI, at his university's medical school, on the mechanical behavior of tissues and antibiotic action of native antibiotic agents on certain bacteria, since it would allow for much higher resolution imaging and quantitative measurements of nanomechanical properties. Both investigators are junior scientists, and the project will also support two graduate students from each institution.