The optimization of the reaction conditions (pH,T,t) to obtain stable copper(II) ion complexes with dextran derivatives were investigated in this paper. A complete synthesis of stable aqueous complexes can be realized with reduced low-molar polysaccharides, at an average molar mass 5000 g mol–1and pH 7.5–8. Fourier-transform IR spectra of polysaccharide dextran and its compounds with copper(II) ion, recorded at room temperature, were analyzed in order to obtain the information about the structure and the conformation of these polymer compounds. The ESR parameters of the spectra indicate the square-planar coordination of Cu(II) ion with four O atoms. Copper(II) complex formation with dextran and its derivatives were analyzed by physicochemical methods. Synthesized complexes of Cu(II) ion with reduced low-molar dextran in comparison with commercial preparations showed the considerably lower acute toxicity (LD501705).

The result of the synthesis and investigation of FTIR spectra of some dextran sulphates and their sodium (Na) salts are presented. A synthesis was conducted (under different reaction parameters) of esters with various degrees of esterification (from 1.0 to 2.3). FTIR investigations were performed on sulphates of low and high molecular hydrogenated dextrans of various molecular masses (Mw of 5000, 7000, 8000, 40000 and 500000). Particular care was taken to determine the degree of linearity of the synthesized dextran sulphates, the conformation of glucopyranosyl units and the way the sulpho groups and the water were bonded in their structures.

Co(II) ion complex compounds were synthesized with reduced dextran (RD) in alkali solutions using CoCl2, 6H2O and isolated in the solid state. UV-VIS spectrophotometric investigations of Co(II) complexes with reduced dextran showed that the complexation of Co(II) ions begins at pH over 7. The formation of Co(II) ion complexes with dextran monomer units was observed at pH 7-13. With increase in solution pH the light absorption maximum of complex solutions shifts to longer wavelengths (bat-hochromic shift) compared with [Co(H2O)6]2+ ion. Dextran complexes with Co(II) ion are formed by the displacement of water molecules from the coordination sphere of cobalt by the OH ligand groups. The spectrophotometric parameters of the investigated complexes are characteristic of a Co(II) ion in octahedral or distorted octahedral coordination with O ligand atoms

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