Polysaccharides functionalized by tryptophan derivatives

Functionalized polysaccharide chosen from the group consisting of the polysaccharides of general formula I:

• the polysaccharide being predominantly composed of glycosidic bonds of (1,4) and/or (1,3) and/or (1,2) type,
• F resulting from the coupling between the connecting arm R and an —OH functional group of the neutral or anionic polysaccharide, being either an ester, thioester, amide, carbonate, carbamate, ether, thioether or amine functional group,
• R being an optionally branched and/or unsaturated chain comprising between 1 and 18 carbons, comprising one or more heteroatoms, such as O, N and/or S, and having at least one acid functional group,
• Trp being a residue of an L and/or D tryptophan derivative, a product of the coupling between the amine of the tryptophan derivative and the at least one acid carried by the R group and/or an acid carried by the anionic polysaccharide,
• n representing the molar fraction of the R groups substituted by Trp and being between 0.05 and 0.7,
• representing the molar fraction of the acid functional groups of the polysaccharides substituted by Trp and being between 0.05 and 0.7,
• i representing the molar fraction of acid functional groups carried by the R group per saccharidic unit and being between 0 and 2,
• j representing the molar fraction of acid functional groups carried by the anionic polysaccharide per saccharidic unit and being between 0 and 1,
• (i+j) representing the molar fraction of acid functional groups per saccharide unit and being between 0.1 and 2,
• when R is not substituted by Trp, the acid or acids of the R group then being carboxylates of a cation, such as Na or K,
• when the polysaccharide is an anionic polysaccharide, when one or more acid functional groups of the polysaccharide are not substituted by Trp, they then being salified by a cation, such as Na or K,
• said polysaccharides being amphiphilic at neutral pH.