Measurements of light scattering changes induced by a strong optical field in solutions of tRNA

Abstract

Changes in light scattering induced by a strong laser beam, as predicted theoretically by Kielich, were measured for unfractionated yeast transfer ribonucleic acid (tRNA) solutions. The vertically polarized electric field of a strong laser pulse (λ = 1060nm) amounted to 4.5 × 103 esu cgs; its duration was 10 nsec. A weak incident laser beam (λ = 630nm) was also polarized vertically and the vertical and horizontal intensity components of the light scattered through 90° at the latter wavelength were measured. These measurements together with previous results from measurements of Rayleigh light scattering and light scattering in a magnetic field permitted evaluation of the tensor of third‐order polarizability (c = 3 × 10−30 esu cgs, c = −373 × 10−30 esu cgs) and the anisotropy of the third‐order polarizability components with its sign (δc = +56 × 10−2, δc = +0.25 × 10−2 for tRNA monomer and aggregate, respectively). The new method described may be useful for studies of macromolecules and macromolecular complexes of biological importance.

Light Scattering and SAXS Study of AOT Microemulsion at Low Size Droplet

“…In this work, the microemulsion system is located in the L 2 region at studied temperatures and compositions investigated. Most works on collective diffusion coefficient of droplets and interactions of droplets have been done mainly on charged macromolecules, [3][4][5][6][7][8][9][10][11][12][13][14][15], for example bimolecular, [3][4][5][6][7][8][9][10], as DNA, proteins and amino acids, micelles, [11], and polymer latexes, [15], in water (as polar solvent) at low ionic strength. The strong, long range electrostatic interactions between the particles or droplets in these systems lead to remarkable structure effects.…”