Biodegradable biopolymers, method for their preparation and functional materials constituted by these biopolymers

A metal ion-adsorbing material comprising a biodegradable biopolymer material that comprises:

• a composite material comprising silk fibroin from wild silkworm and keratin from wool,
• wherein the keratin from wool is reduced keratin or S-carboxymethyl keratin.

A sustained release carrier for a useful substance comprising a biodegradable biopolymer material that comprises:

• a composite material comprising silk fibroin from wild silkworm and keratin from wool,
• wherein the keratin from wool is reduced keratin or S-carboxymethyl keratin.

A substrate for growth of biological cells comprising a composite material comprising silk fibroin from wild silkworm and keratin from wool, wherein the substrate is used for the growth of biological cells, and wherein the keratin from wool is reduced keratin or S-carboxymethyl keratin.

A method for the preparation of a membrane-like biodegradable polymer material comprising silk fibroin from a wild silkworm and keratin from wool, wherein the keratin is reduced keratin or S-carboxymethyl keratin, comprising the steps of:

• (a) applying, onto the surface of a substrate, an aqueous mixed solution comprising an aqueous solution of silk fibroin from a wild silkworm and an aqueous solution of keratin from wool, wherein the keratin from wool is reduced keratin or S-carboxymethyl keratin, and
• (b) cast drying the applied solution to form the membrane-like biodegradable biopolymer material, wherein the aqueous mixed solution is prepared by uniformly admixing the constituents of the aqueous mixed solution by stirring them such that they do not undergo any gelation, precipitation and/or coagulation reaction.

A method for the preparation of a powdery biodegradable biopolymer material comprising silk fibroin from a wild silkworm and keratin from wool, wherein the keratin is reduced keratin or S-carboxymethyl keratin, comprising the steps of:

• (a) freezing an aqueous mixed solution comprising an aqueous solution of silk fibroin from wild silkworm and an aqueous solution of keratin from wool, wherein the keratin from wool is reduced keratin or S-carboxymethyl keratin, and wherein the aqueous mixed solution is prepared by uniformly admixing the constituents of the mixed aqueous solution by stirring them such that they do not undergo any gelation, precipitation and/or coagulation reaction, and
• (b) drying the frozen aqueous solution under a reduced pressure to form the powdery biodegradable biopolymer material.

A method for the preparation of a gel-like biodegradable biopolymer material comprising silk fibroin from a wild silkworm and keratin from wool, wherein the keratin is reduced keratin or S-carboxymethyl keratin, comprising the steps of:

• (a) adjusting the pH value of an aqueous mixed solution comprising an aqueous solution of silk fibroin from wild silkworm and an aqueous solution of keratin from wool, wherein the keratin is reduced keratin or S-carboxymethyl keratin, to a pH level within the acidic pH range, and
• (b) entirely coagulating the aqueous mixed solution to give the gel-like biodegradable biopolymer material.