Enzymatic Digestion of Single DNA Molecules Anchored on Nanogold-Modified Surfaces

Abstract

To study enzyme–DNA interactions at single molecular level, both the attachment points and the immediate surroundings of surfaces must be carefully considered such that they do not compromise the structural information and biological properties of the sample under investigation. The present work demonstrates the feasibility of enzymatic digestion of single DNA molecules attached to nanoparticle-modified surfaces. With Nanogold linking DNA to the mica surface by electrostatic interactions, advantageous conditions with fewer effects on the length and topography of DNA are obtained, and an appropriate environment for the activities of DNA is created. We demonstrate that by using Dip-Pen Nanolithography, individual DNA molecules attached to modified mica surfaces can be efficiently digested by DNase I.

Automated Manipulation of Micro-Nano Objects with SPM by Using L1 Adaptive Controller

“…As a matter of fact, typically, freshly cleaved mica is utilized as the substrate for manipulation experiments because of its relatively smooth and hard surface [17]. The root mean square (RMS) roughness of the mica surface isin the order of0.01 nm [19]. Hence, it is believed to be more convenient and efficient to maintain a desired d z .…”