Amphiphilic polysaccharides, polysaccharide-based hydrogels, and methods of manufacture
A method for the synthesis of alkyl ω-carboxy(hydroxyethyl) polysaccharides is described. The method includes methylating or ethylating a polysaccharide or providing a methylated or ethylated polysaccharide, hydroxyethylating the methylated or ethylated polysaccharide, and oxidizing the hydroxyethylated polysaccharide to form the ω-carboxy(hydroxyethyl) polysaccharide. A method for the synthesis of oxidized polysaccharides is also described. The method includes hydroxypropylating a polysaccharide and oxidizing the hydroxypropylated polysaccharides. A method for the production of a solid capable of forming a hydrogel is also described. The method includes combining a first solution comprising an oxidized oligo(hydroxypropyl) polysaccharide bearing one or more ketone groups with a second solution comprising an amine substituted polysaccharide to form a third solution, and removing solvent from the third solution to form the solid, or adding an additional solvent to the third solution to precipitate the solid. Novel polysaccharides and hydrogels prepared according to these methods are also described.
1. A method for the synthesis of oxidized polysaccharides, comprising:
hydroxypropylating a polysaccharide; and
oxidizing the hydroxypropylated polysaccharide;
wherein the polysaccharide is dextran;
wherein the oxidizing comprises selectively oxidizing terminal secondary alcohols of the hydroxypropylated polysaccharide to ketones; and
wherein the oxidizing comprises reacting the hydroxypropylated polysaccharide with NaOCl or NaOBr.
2. The method of claim 1 , further comprising reacting the oxidized hydroxypropylated polysaccharide with a primary amine to form an amine-conjugated oxidized polysaccharide.
3. The method of claim 1 , wherein the oxidizing is performed at a pH of about 7 or 7.4.
4. The method of claim 1 , wherein the oxidizing is performed in the presence of a buffer.
5. The method of claim 4 , wherein the buffer is a phosphate buffer.
6. The method of claim 5 , wherein the phosphate buffer has a pH of 7.
7. A method for the synthesis of oxidized polysaccharides, comprising:
oxidizing a hydroxypropylated polysaccharide;
wherein the oxidizing comprises selectively oxidizing terminal secondary alcohols of the hydroxypropylated polysaccharide to ketones;
wherein the polysaccharide is dextran; and
wherein the oxidizing comprises reacting the hydroxypropylated polysaccharide with NaOCl or NaOBr.
8. The method of claim 7 , wherein the oxidizing is performed at a pH of about 7 or about 7.4.
9. The method of claim 7 , wherein the oxidizing is performed in the presence of a buffer.
10. The method of claim 9 , wherein the buffer is a phosphate buffer.
11. The method of claim 10 , wherein the phosphate buffer has a pH of 7.
12. The method of claim 7 , further comprising reacting the oxidized hydroxypropylated polysaccharide with a primary amine to form an amine-conjugated oxidized polysaccharide.
13. A method for the synthesis of oxidized polysaccharides, comprising:
oxidizing a hydroxypropylated polysaccharide; and
reacting the oxidized hydroxypropylated polysaccharide with a primary amine to form an amine-conjugated oxidized polysaccharide;
wherein the oxidizing comprises selectively oxidizing terminal secondary alcohols of the hydroxypropylated polysaccharide to ketone, wherein the polysaccharide is dextran; and
wherein the oxidizing comprises reacting the hydroxypropylated polysaccharide with NaOCl.
14. The method of claim 13 , wherein the oxidizing is performed at a pH of about 7 or about 7.4.
15. The method of claim 13 , wherein the oxidizing is performed in the presence of a buffer.
16. The method of claim 15 , wherein the buffer is a phosphate buffer.