Atomic force microscopy: a powerful tool for high-resolution imaging & force sensing

Atomic force microscopy (AFM) was invented by Binnig, Quate and Gerber in 1986 and since then it has evolved as a powerful imaging technique to obtain nanometer-resolved topographic images of materials. AFM has emerged as the only technique capable of real-time imaging of the surface of a living cell at nano-resolution. The principle of AFM is very simple. In brief, it uses a highly sensitive and flexible cantilever as force sensor. The sample surface is raster scanned by the cantilever with a sharp tip at the end and the interaction force between the tip and the sample is measured by the degree of deflection of the cantilever. The cantilever deflection is detected by a laser-beam bounce method. I will highlight in this talk various modes of AFM imaging of biological and non-biological samples. Furthermore, AFM can be solely used to apply or sense forces on single molecules. In the past decade or so, this property of AFM has been utilized to apply forces to chemical and biological polymers to study their force dependent chemistry and biology. I will highlight some of the AFM results from our lab on single molecule chemistry and biology. 



 About Dr. A.S.R. Koti : 

Dr. Koti got his MSc in chemistry from University of Hyderabad in 1997 and PhD from TIFR in 2003. Subsequently, he pursued his post-doctoral studies at Columbia University in New York, USA. He came back and joined TIFR in 2008 as a Reader. His research interests are in using novel experimental techniques to understand the chemistry and biology at the single molecule level.