Force microscopy: application to soft matter

Atomic force microscopy (AFM) has been shown to be a good means of investigating matter at the nanometer scale. Here, we use it on one hand to determine the structure of adsorbed biological macromolecules such as DNA at high resolution on solid surfaces in liquid, and on the other hand as a force probe. In this case, we try to extract the relevant information from the complicated force profiles. We have studied the characterisation of specific molecular interactions. Our study reveals that in the presence of multiple parallel bonds with high rebinding probability, the force increases with decreasing speed velocity. We propose that the rebinding via the fluctuation of the linker is responsible for the observed behaviour.