Method for chemically modifying biopolymer and polypeptide

A method for producing a chemically modified biopolymer or polypeptide, the method comprising:

• chemically modifying a biopolymer or polypeptide in a reaction solution containing an organic fluorine compound, wherein the organic fluorine compound is an alcohol or a ketone,
• wherein the chemical modification is (i) a chemical modification which is made via amide bond, ester bond, ether bond or urethane bond, (ii) an intermolecular cross-linking reaction, or (iii) an intramolecular cross-linking reaction,
• wherein the biopolymer or polypeptide is reacted with at least one compound (A) selected from the group consisting of an acid anhydride, an acid chloride and an epoxide, each having a predetermined functional group, and a compound having a dithiocarbamyl group, to introduce the functional group or the dithiocarbamyl group to the biopolymer or polypeptide, and/or
• the biopolymer or polypeptide is reacted with a crosslinking agent (B) to crosslink the biopolymer or polypeptide, wherein the crosslinking agent is at least one selected from the group consisting of formaldehyde, glutaraldehyde, carbodiimide, cyanamide, vinyl sulfone, terephthalic acid and diepoxide, and
• wherein the biopolymer is selected from the group consisting of a protein and a polysaccharide.