Bio-nanotechnology of DNA

A method has been developed to use high-intensity electrostatic field created in a microfabricated electrode system to stretch DNA molecule and immobilize onto a predetermined location on a solid surface. Once immobilized, we can apply operations to aimed position on aimed molecule. It has been shown that the desired portion of stretched DNA can be mechanically dissected, picked up, and amplified. A microstructure has been developed in which DNA is stretched and held at both molecular termini, leaving middle part without contact to a solid surface. This allows DNA enzymes to freely interact with the immobilized DNA. Using the structure, molecular surgery of DNA is demonstrated, where DNA cutting enzyme is immobilized on a microparticle, which is laser-manipulated and made into contact with stretched DNA, so that the enzymatic reaction occurs at the contact point. The structure also enables the observation of DNA-protein interaction on real-time, single-molecule level, for the use for optical mapping of DNA sequence, as well as in basic investigations such as the motion of,a restriction enzyme along DNA as it searches the restriction site.