The i.r. spectra were obtained and analysed for non-deuterized and deuterized films of poly U, multilayer Langmuir films of the complex of poly U with octadecylamine and octadecylamine in the solid state and in non-polar solvents. It was found that on complexing of poly U with an aliphatic amine situated on the surface of the aqueous or water-salt phase, molecular-ionic conversion of poly U does not occur and the nucleic base in the complex is in molecular form. A method is devised for determining the stoichiometry of the complex and an evaluation of the stoichiometry of the multilayer Langmuir film investigated is presented. It was found that during complexing, instead of the bands of the valent and deformation vibrations of the amino group of octadecylamine, bands appear characteristic of the ammonium + NH3 group. It is shown that in the complex the + NH3 groups of octadecylamine are bound by strong H bonds and electrostatically to the phosphate groups of the the polynucleotide and also hydrogen bonds with the carbonyl groups of nucleic bases and the oxygen of the ribose rings. A model of a multilayer Langmuir film of the complex is proposed in which one may isolate, firstly, the hydrophilic channel formed by the + NH3 groups of the aliphatic amine and some fragments of the polynucleotide chain (in it the strongest hydrating centres are isolated and the virtual absence of hydration by the phosphate groups is shown) and, secondly, the aliphatic bilayer insensitive to the water content.
|Number of pages||10|
|Journal||Biophysics (Russian Federation)|
|Publication status||Published - 1994|