A sofware-based controller for single-molecule experiments using an atomic force microscope integrated with a magnetic manipulator

Abstract

Single-molecule methods have become powerful tools to study biomolecules because they allow direct observation of the complex molecular kinetics. Among them atomic force microscope (AFM) is one of the most popular tools due to its capability of nanomanipulations. Various information ofbiomolecular bonds such as force level, life time, length and their relationship can be derived by pulling molecules in different ways with AFM. In this thesis, a software based PID controller for force clamped experiment that pulls the molecules in a constant force is developed with LabVIEW. Then the controller is verified and characterized in piezo actuation mode and magnetic actuation mode using a customized AFM. Lastly, force clamped experiments with heparin-FGF2 and biotin-streptavidin are performed with the controller and the probabilities of their lifetimes are analyzed statistically.