Reductive amination of vinyl acetate and acrolein copolymers by polymixin B1 and the complexing properties of the resulting conjugates

Abstract

The reaction of reductive amination of vinyl acetate and acrolein copolymers by the cyclic polypeptide polymyxin B1 was investigated. The synthesis was carried out using copolymers with a molecular weight from 40 000 to 120 000 containing acrolein and vinyl alcohol units in amounts of up to 5-7 wt.% and 12 wt.%, respectively. The degree of peptide addition to the polymers is established to increase proportionally with a decrease in the molecular weight of the copolymers from 120 000 to 40 000 and an increase in the proportion of hydroxyl groups from 1 to 12 wt.%. The maximum degree of attachment was 7 wt.%. The (co)polymer-peptide conjugates are readily soluble in volatile organic solvents. During the solvent evaporation, thin transparent films are formed from their diluted alcohol or acetone solutions, firmly adhering to the surface of the glasses. A study of the biological properties (complexation) of a covalently bound peptide has shown the immobilisation of the conjugates on the glass surface without the effect on its interaction with bacterial lipopolysaccharides. The degree of extraction of lipopolysaccharides from biological fluid amounted to 80-90%. The modified polymers may be of interest as secondary reagents for a selective isolation and concentration of lipopolysaccharides from biological or technological media with a view of their subsequent study.