Statics and Dynamics of Single DNA Molecules Confined in Nanoslits

de Gennes provided the scaling predictions for the linear polymer chain trapped in slit with dimension close to the Kuhn length decades ago; however, it has yet to be compared with experiments. We have fabricated nano-slits with vertical dimension similar to the Kuhn length of ds-DNA, $\sim $ 100nm, using standard photolithography. Single DNA molecules with length range from 2 to75 micrometers were successfully inject into the slits and the Brownian motions were imaged by fluorescence microscopy. The distributions of the radius of gyration and the two-dimensional asphericity were measured and it is found that the DNA exhibit highly anisotropic shape distribution. The scaling exponents for the chain extension and the center-of-mass diffusion coefficient will also be discussed.