Light scattering from wormlike chains with excluded volume effects

✍ Scribed by Phillip Sharp; Victor A. Bloomfield

• Publisher: Wiley (John Wiley & Sons)
• Year: 1968
• Tongue: English
• Weight: 467 KB
• Volume: 6
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1968.360060814

✦ Synopsis

This paper reports a calculation of the angular dependence of light scattering from wormlike chains with excluded volume effects. The Daniels distribution function, modified for excluded volume effects, is used to compute averages for scattering elements separated by contour lengths which are long with respect to the persistence length of the rhain. An expansion in terms of exactly known moments of the distribution for the wormlike coil without excluded volume is used for short contour lengths. The results are applied to scattering from calf thymus ( M = 18.1 X 106) and T7 (134 = 25.4 X 10') DNA. It is demonstrated that the same value: of excluded volume parameter (e = 0.11) and statistiral segment length (l/A' = 900 A) which explain the sedimentation and viscosity behavior of DNA also account satisfactorily for the scattering behavior. Molecular weights and root-mean-square radii estimated by extrapolation from scattering data obtained in the angular region from 10" to 25" will he &lo% too large for DNA of molecular weight 20 x 106-30 X 106.