Handling of a single DNA molecule using electric field and laser beam

An accurate handling of a single DNA molecule will support a novel technique for sequencing of large DNA. The opto-electrostatic micromanipulation (OEMM) has been applied to handle a single DNA molecule. The DNA molecule frequently changes its position and its shape due to Brownian motion, therefore precise handling becomes difficult. Gelation of the sample by agarose gel is effective to suppress Brownian motion. Fundamental handling techniques for a single DNA molecule in agarose gel were demonstrated as follows: 1) fixation with stretched shape, 2) cutting by ultraviolet laser, and 3) isolation and recovery into the capillary (inner diameter 18 mu m). Amplification of the recovered DNA fragment by the PCR (polymerase chain reaction) method is the next step of this study. This micromanipulation technique may contribute for accelerating the time needed for DNA sequencing.