31-01-2009, 12:31 AM
In this paper a novel method for the space resolved dissection (molecular surgery) of DNA using electrostatic molecular manipulation is proposed and demonstrated. In conventional biochemistry DNA cutting enzymes and DNA are mixed in water, so the cutting reactions occur only by stochastic chances. In contrast, the present method is based upon a physical manipulation and enables the deterministic cutting of DNA at any position on a DNA molecule. In order to realize this space resolved cutting, the target DNA is stretched straight by electrostatic orientation, and anchored on to a solid surface by dielectrophoresis using a high intensity high frequency field generated in microfabricated electrodes. The electrodes are energized by a high frequency power supply, to create 1MV/m, 1MHz, and electrostatic field in the gap. DNA supplied in the gap is stretched straight by the high intensity field and both termini of the DNA strand are pulled in to the electrode edges. As a result the strand is anchored at both molecular ends bridging over two adjacent electrodes, but the middle part is free, so that enzyme can bind and react. The molecular surgery presented in this paper is expected to realize space resolved molecular operations, not only limited dissection, but also chemical modifications, or even insertion of genes may become possible in future.