Two-Dimensional Smectic Ordering of Linear DNA Chains in Self-Assembled DNA-Cationic Liposome Mixtures
نویسندگان
چکیده
We report a synchrotron x-ray scattering study of linear DNA chains and cationic liposome mixtures which spontaneously self-assemble into a coupled two-dimensional (2D) smectic phase of DNA chains imbedded between lipid bilayers of a 3D smectic phase. The DNA peak is quantitatively described by anisotropic exponentially decaying chain-chain correlations. The measured interchain compressibility modulus Bsdd as a function of the interhelical spacing d of the 2D smectic, with 25 , d , 60 Å, is not described by hard core repulsions but, rather, is dominated at larger spacings d . 35 Å by long-range electrostatic repulsions. [S0031-9007(97)04054-4]
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