DNA molecules resolved by electrical double layer force spectroscopy imaging

This paper deals with spatially resolved force spectroscopy applied to the imaging of the electrical double layer (EDL) force. It is focused on an important point that has not been elucidated yet, the resolution that can be achieved. For this purpose, single plasmid DNA molecules have been studied with an atomic force microscope operated in the force spectroscopy imaging mode. With this approach, important quantities deduced from the force spectra can be simultaneously mapped along with the topography image. Single DNA molecules have been probed obtaining a lateral resolution in the EDL force similar to that of the topography. (c) 2008 American Institute of Physics.