PARTIAL AND CHARGE STRUCTURE FUNCTIONS OF MONODISPERSE DNA FRAGMENTS IN SALT FREE AQUEOUS-SOLUTION

Observations of the partial structure functions and the charge structure function are reported for an aqueous solution of monodisperse rodlike DNA fragments, without added simple salt. In the reciprocal space interval q greater-than-or-equal-to 0.075 angstrom-1, the neutron scattering data can be fitted by the correlation functions derived from the exact solution of the Poisson-Boltzmann equation in the cell model. The fit is equally good for all partial structure functions as well as the charge structure function. The cell model seems to be appropriate for this kind of solution.