Manufacture and use of modified polysaccharide chitosan bonds and a process to improve the preparation of HES-medicinal substance compounds

A method for preparing a biocompatible material for use in artificial blood vessels, vascular implants, artificial heart valves, heart mitral valves, tendons and ligament substitutes, cartilage substitutes, patches for closing undesirable openings during surgical interventions and wound covers;

• surgical adjuvants, disposable articles that are employed intracorporeally on a short-term basis, catheters, catheter tubes, suture material, biodegradable suture material, syringes, extracorporeal blood tubes, blood bags or bags for solutions for intravenous applications, and bag sheets;
• or as components in medical devices, the method comprising:
• providing a bonding product in the biocompatible material, the bonding product consisting of:
• m molecules of a polysaccharide X linked with a polysaccharide A through a linkage,
• wherein said polysaccharide A is selected from the group of chitins or chitosans having a degree of deacetylation of not more than about 75%,
• m is an integer of from 1 to 10,000, and
• the linkage between polysaccharide X and polysaccharide A is an amine linkage, amide linkage, or both, wherein said polysaccharide X is starch, amylose, amylopectin, or combinations thereof, which is partially or completely substituted with substituents selected from the group consisting of hydroxyethyl groups and carboxymethyl groups, wherein said bonding product is substituted by having residues of formula (II) covalently bound to polysaccharide X and by having residues of formula (III) covalently bound to polysaccharide A, wherein formula (II) is —Z1cR1 and formula (III) is —Z2dR2 and
• R1 is a pharmaceutically active molecular residue,
• R2 is a pharmaceutically active molecular residue, and
• R1 and R2 may be the same or different, and
• wherein
• Z1 is a linker that is covalently bound to both R1 and polysaccharide X,
• Z2 is a linker that is covalently bound to both R2 and polysaccharide A,
• c=1 or 0,
• d=1 or 0, and
• wherein
• the molar ratio of the residue of formula (II) to polysaccharide X is a,
• the molar ratio of the residue of formula (III) to polysaccharide A is b,
• a is an integer of up to 1000,
• b is an integer of up to 1000, and
• both a and b are not zero.