Imaging and Force Spectroscopy on DNA

Abstract

Imaging of single DNA molecules has reached the best spatial resolution by means of dynamic force mode. Amplitude and Frequency Modulation modes at room and low temperature in UHV indicate semi-contact or non-contact as the best modes to achieve high resolution on such small biological molecules. A step forward to more quantitative results is single point force spectroscopy. The force and potential evaluation from the experimental curves evidences the contrast between substrate and DNA and suggests the Non Contact AFM as a possible tool for molecular recognition.