New research demonstrates that novel probe technology based on flexible membranes can replace conventional atomic force microscopy (AFM) cantilevers for applications such as fast topographic imaging, quantitative material characterization and single molecule mechanics measurements.
In addition to the standard AFM topography scan, these novel probes simultaneously measure material properties including adhesion, stiffness, elasticity and viscosity.
Our probes attach directly to AFM systems currently on the market and can collect topography measurements at least 50 times faster than traditional cantilevers because they use electrostatic forces between the membrane and an electrode to move the tip, said Levent Degertekin, a professor in the George W. Woodruff School of Mechanical Engineering at Georgia Tech. The research team also includes Guclu Onaran and Hamdi Torun, graduate students in the Georgia Tech School of Electrical and Computer Engineering.
Details of the novel force sensing integrated readout and active tip (FIRAT) probe and its biological applications were presented at the American Physical Society meeting in March. This research was funded by the National Institutes of Health and the National Science Foundation.
In current AFM systems, the sample surface is scanned by a cantilever with a sharp tip just a few nanometers in diameter at the end. An optical beam is bounced off the cantilever tip to measure the deflection of the cantilever as the sharp tip moves over the surface and interacts with the material being analyzed to determine the topography of the surface.
The new probe replaces the cantilever with a drum-like membrane from which a tip extends to scan the material sample. In one scanning mode, as the tip moves above a surface, it lightly taps the material. With each tap, the instrument gathers precise information about both the tips position and the forces acting on it, sensing the shape of the
|Contact: Abby Vogel|
Georgia Institute of Technology Research News