title: Optical properties of CsDNA films as a function of hydration.
abstract: The refractive indices of wet-spun films of CsDNA have been measured for light polarized parallel and perpendicular to the helical axis as a function of relative humidity (RH). These data have been combined with previously published data (Biopolymers 30 (1990) 877-887) for the volume per base pair and water content as a function of RH in order to extract the optical polarizabilities. This work was motivated by the study of Weidlich et al. (Biopolymers 26 (1987) 439-453) who reported a approximately 35% increase at the A-to-B transition in the parallel and perpendicular polarizabilities of NaDNA. In contrast, a much smaller increase in the polarizabilities of CsDNA is found near the A-to-B transition: approximately 12% for the perpendicular direction and < or = 4% for the parallel direction.
authors.affiliation: Department of Physics and Astronomy, University of Toledo, OH 43606.
authors.forename: P J
authors.initials: PJ
authors.lastname: Adams
authors.forename: M L
authors.initials: ML
authors.lastname: VanSteenberg
authors.forename: S A
authors.initials: SA
authors.lastname: Lee
authors.forename: A
authors.initials: A
authors.lastname: Rupprecht
mesh_terms: D016880:Anisotropy; D002586:Cesium; D004247:DNA / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D012031:Refractometry; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water; D002586:Cesium; D004247:DNA