Single Molecule Recognition by AFM Force Spectroscopy: From Transcriptional Regulation to Supramolecular Chemistry

Robert Ros

Experimental Biophysics & Applied Nanosciences, Physics Faculty, Bielefeld University




Specific binding forces between single receptor and ligand molecules can be investigated in dynamic force spectroscopy experiments by atomic force microscopy (AFM) revealing details of the interaction mechanism, the kinetics of the reaction and the energy landscape of the binding. The ability to measure inter- and intramolecular forces with piconewton-, nanometer- and millisecond resolution allows investigation of single ligand-receptor interaction in a broad affinity range from 10-5 M to 10-15 M (Kd) at a discrimination level of single point mutations. Recent single molecule experiments from biological transcriptional regulators (protein-DNA), [1-3], specific synthetic bioorganic interaction (peptide-DNA) [4], and supramolecular guest-host interaction (cation-calixarene) [5] will be presented and discussed