Saratov Fall Meeting 2015 OPTICAL PROPERTIES OF CHITOSAN IN AQUEOUS SOLUTIONS OF L- AND D-ASCORBIC ACIDS Olga N. Malinkina* 1,2, Anna B. Shipovskaya 1,2, Olga F. Kazmicheva Institute of Chemistry, Saratov State University 2 - Research and Education Institution of Nanostructures and Biosystems, Saratov State University

Abstract For most biologically active compounds there is a close correlation between biological activity and their spatial structure, which is used to establish by the optical methods, in particular spectropolarimetry, based on the phenomenon of optical isomerism. In this study optical activity of chitosan solutions in different solvents by spectropolarimetric method was investigated. It was found that the spectra of optical rotation of chitosan solutions in ascorbic acid in significantly different in magnitude and sign from chitosan solutions in other solvents.

for Low Molecular Substances Quantum-mechanical theory of optically isotropic and anisotropic media for Low Molecular Substances Quantum-mechanical theory of optically isotropic and anisotropic media for Macromolecular Substances Semi-empirical methods of calculation for Macromolecular Substances Semi-empirical methods of calculation Optical purity Concentration Temperature Nature of the solvent Wavelength The configuration of a chiral center  INTERFERENCE of the CHIRAL CENTERs of the CHAINs  CHAIN CONFORMATION (MOLECULAR STRUCTURE)  STEREOREGULARITY (COPOLYMERS) 3

4 Biospecificity Optical activity Biocompatibility The ability to form polyelectrolyte complexes Antioxidant properties Biospecificity Optical activity Biocompatibility The ability to form polyelectrolyte complexes Antioxidant properties

Formula Structural formula М, at. un. Identification, using рК L-Ascorbic Acid γ-lactone 2,3- dihydro-L-gulonic acid C6H8O6C6H8O6C6H8O6C6H8O6 176 Е300 antioxidant D-Ascorbic Acid γ-lactone 2,3- dihydro-D-gulonic acid –23 D-Lactic Acid α-hydroxy- propionic acid C3H6O3C3H6O3C3H6O3C3H6O3 90 Е270 preservative 3.8 –2.6 Succinic Acid ethan-1,2- dicarboxylic acid C4H6O4C4H6O4C4H6O4C4H6O4 118 Е363 antioxidant −5 * *

(deg·ml·dm -1 ·gram -1 ) or (deg·cm 2 ·decagram -1 ) α – measured angle of optical rotation of the solution, degree α 0 – measured angle of optical rotation of the solvent, degree С п – polymer concentration in solution, g/dl l – pathlength, dm Biot’s Law 6 The spectra of the optical activity of the solutions were recorded on an automatic spectropolarimeter PolAAr 3001 by Optical Activity Ltd (GB) in the wavelength range λ = nm in a thermostated cell at 25°C.

L - ascorbic acid D - ascorbic acid Chitosan solution in D-ascorbic acid Chitosan solution in D-ascorbic acid Chitosan solution in L-ascorbic acid Chitosan solution in L-ascorbic acid 7 λ, nm

in different molar relationships chitosan : ascorbic acid Chs : L-Asc A= 1 : Chs : L-Asc A= 1 : Chs : L-Asc A= 1 : Chs : L-Asc A= 1 : 1 1’ - Chs : D-Asc A= 1 : 2 2’ - Chs : D-Asc A= 1 : 1 1’ - Chs : D-Asc A= 1 : 2 2’ - Chs : D-Asc A= 1 : 1

С Chs = 0.3 g/dl С Acid = 1.0 – 10.0 g/dl In the Ascorbic Acid In the Succinic Acid In the Lactic Acid = +93 = – 14 = – 23 9 λ, nm

Conclusions Optical properties of solutions of CHs in ascorbic, lactic and succinic acids were studied by method of ORD. The essential differences in the values ​​ of specific optical rotation of chitosan solution in different solvents were found. Values ​​ of specific optical rotation [α] 25 λ for the chitosan solution in ascorbic, lactic acid succinic acids were +93, -23 and -14 respectively. The no essential differences in the values ​​ of specific optical rotation of chitosan solution in L- and D-ascorbic acids were found. The influence of molar ratio on the optical activity [α] of chitosan solution of ascorbic acid was found. The interaction between chitosan and ascorbic acid is spatial different from interaction with other organic and nonogranic acids. Perhaps this explains the synergistic effect high therapeutic action of multicomponent systems based on chitosan and ascorbic acid.