Modified collagen compound and method of preparation

• US 4,883,864 A
• Filed: 10/28/1988
• Issued: 11/28/1989
• Est. Priority Date: 09/06/1985
• Status: Expired due to Term

• Current Assignee: 3M Company
• Original Assignee: 3M Company
• Inventors: Scholz, Matthew T.
• Primary Examiner(s): Kight, John
• Assistant Examiner(s): Nutter, Nathan M.
• Application Number:
  US07/264,062
• Time in Patent Office: 396 Days
• Field of Search: 530/356, 530/353, 530/402, 128/DIG. 8, 604/51, 514/21, 514/801, 514/912, 523/113, 3/1
• US Class Current: 530/356
• CPC Class Codes: A61F 2310/00365 Proteins; Polypeptides; Degradation products thereof
• CPC Class Codes: A61L 27/24 Collagen
• CPC Class Codes: C07K 14/78 Connective tissue peptides, e.g. collagen, elastin, laminin, fibronectin, vitronectin or cold insoluble globulin [CIG]
• CPC Class Codes: C08H 1/06 derived from horn, hoofs, hair, skin or leather
• CPC Class Codes: Y10S 128/08 Collagen

Abstract

Chemically-modified collagen is prepared by reacting native collagen with a di or tri-carboxylic acid halide, di or tri-sulfonyl halide, di or tri-anhydride, or di or tri-reactive active ester coupling agent. The reaction is done in a controlled manner so that the degree of cross-linking is limited. Any remaining lysine epsilon amino groups present in the coupled collagen product may be converted to ureido, β-malicamino carboxyamido or sulfonamido groups by isocyanate, epoxy succinic acid, acid halide, anhydride, sulfonyl halide or active ester aminemodifying agents. The resultant soluble product when dissolved in a physiological buffer provides a viscoelastic solution having therapeutic application in a variety of surgical procedures, particularly in ophthalmic surgery. This viscoelastic solution "melts," i.e., exhibits a dramatic loss of viscosity, when subjected to temperatures of between 32° and 48° C. The resultant insoluble product is suspended in physiological buffer and useful in tissue augmentation. The suspension containing the insoluble product exhibits a dramatic loss in viscosity at temperatures between about 40° and 70° C.

Claims

1. A chemically-modified collagen compound comprising at least two native collagen molecules coupled at least one lysine epsilon amino group present on each of said collagen molecules by a coupling group, said coupling group comprising at least two moieties selected from the group consisting of carbonyl and sulfonyl groups, wherein non-coupled lysine epsilon amino groups are linked to amine modifying groups selected from groups of the formula ##STR8## wherein R is a substituted or unsubstituted C_1-8 aliphatic, C_5-8 alicyclic, or C_6-10 aromatic group having 0-5 heteoatoms, and the formula ##STR9## and its metal salts.

2. The compound of claim 1 wherein at least 60% of the non-coupled lysine epsilon amino groups are linked to the amine modifying groups.

3. The compound of claim 1 wherein the amine modifying groups are groups of the formula ##STR10## wherein R is a substituted or unsubstituted C_1-8 aliphatic, C_5-8 alicyclic, or C_6-10 aromatic group having 0-5 heteroatoms.

4. The compound of claim 3 wherein R is C_1-8 alkyl, C_5-8 cycloalkyl, C_6-10 aryl, C_6-10 substituted aryl, or C_6-10 aralkyl.

5. The compound of claim 4 wherein R is butyl.

6. The compound of claim 1 wherein the amine modifying groups are groups of the formula ##STR11## or its metal salts.

7. A collagen fraction comprised of collagen molecules, about 10-80% of which comprises the compound of claim 6.

8. A viscoelastic collagen solution comprising about 0.5-5.0% by weight of the collagen fraction of claim 7 dissolved in a physiological buffer solution.

9. A viscoelastic collagen solution comprising about 0.5 to 5.0 percent by weight of the collagen compound of claim 6 dissolved in a physiological buffer solution, wherein the coupling group is present in said chemically-modified collagen compound to such an extent that a 2 percent by weight solution of said collagen compound in said physiological buffer has a melt temperature of between about 32°

C. and 48°

C.

10. A collagen fraction comprised of collagen molecules, about 10-80% of which comprise the compound of claim 1.

11. A chemically modified collagen composition comprising about 0.5-5.0% by weight of the collagen fraction of claim 10 suspended in a physiological buffer solution.

12. A chemically modified collagen composition comprising about 0.5 to 5.0 percent by weight of the collagen compound of claim 1 suspended in a physiological buffer solution.

13. The chemically modified collagen composition of claim 12 wherein the coupling group is present in said chemically-modified collagen compound to such an extent that a 2 percent by weight suspension of said collagen compound in said physiological buffer has a melt temperature of between about 40°

C. and 70°

C.

14. The chemically modified collagen composition of claim 12 wherein said coupling group is --CO(CH₂)₂ --CO-- or--CO(CH₂)₃ --CO--, and said modifying group is --CONH(CH₂)₃ CH₃.

15. The chemically modified collagen composition of claim 12 wherein said coupling group is --CO(CH₂)₃ --CO-- or--CO(CH₂)₂ --CO--, and said modifying group is --CHCOOH--CHOH--COOH.

20. A method of achieving hemostasis comprising placing an effective amount of the chemically-modified collagen compound of claim 1 in contact with a bleeding wound.

21. A method of augmenting soft tissue comprising placing an effective amount of the chemically-modified collagen composition of claim 11 in contact with the augmentation site.

16. A method of making a chemically-modified collagen compound comprising the steps of

(a) adding to an aqueous solution of at least about 0.05 percent by weight native collagen, a coupling agent in an amount equal to about 1 to 600 moles of coupling agent per mole of native collagen, said coupling agent selected from the group consisting of di- and tri-carboxylic acid halides, di- and tri-sulfonyl halides, di- and tri-anhydrides, di- and tri-reactive active esters, and compounds having at least two moieties selected from the group consisting of carboxylic acid halide, sulfonyl halide, anhydride and active ester;

(b) reacting said native collagen and said coupling agent at a pH of above about 8 and at a temperature of between about 0 and 35°

C., for a time period sufficient to either react or hydrolyze substantially all of said coupling agent;

(c) adding to said reaction mixture a mono-reactive amine-modifying agent, said amine-modifying agent being selected from agents of the formula

space="preserve" listing-type="equation">O═

C═

N--R

wherein R is a substituted or unsubstituted C_1-8 aliphatic, C_5-8 alicyclic, or C_6-10 aromatic group having 0-5 heteroatoms, and epoxy succinic acid in an amount equal to at least about 100 moles of amine-modifying agent per mole of native collagen; and

(d) conducting the amine-modification reaction at a pH of greater than about 8 and at a temperature of between about 0 and 35°

C., for a time period sufficient to either react or hydrolyze substantially all of said amine-modifying agent

17. The method of claim 16 wherein said coupling agent is selected from the group consisting of terephthaloyl chloride;

bicyclo-(2,2,)-oct-7 -ene-2,3,5,6-tetracarboxylic-2,3,5,6-dianhydride;

1,2,4,5-benzenetetracarboxylic dianhydride;

p-fluorosulfonylbenzenesulfonyl chloride; and

wherein the pH of the reaction mixture is initially maintained at about 3 to about 5.5 before raising the pH to above about 8.

18. A method of making a chemically-modified collagen compound comprising the steps of:

(a) adding to an aqueous solution of at least about 0.05 percent by weight native collagen, a coupling agent in an amount equal to about 1 to 600 moles of coupling agent per mole of native collagen and a mono-reactive amine-modifying agent in an amount equal to at least about 50 moles of amine-modifying agent per mole of native collagen;

said coupling agent selected from the group consisting of di- and tri-carboxylic acid halides, di- and tri-sulfonyl halides, di- and tri-anhydrides, di- and tri-reactive active esters and compounds having at least two moieties selected from the group consisting of carboxylic acid halide, sulfonyl halide, anhydride and active ester; and

wherein said amine-modifying agent is selected from groups of the formula

space="preserve" listing-type="equation">O═

C═

N--R

wherein R is a substituted or unsubstituted C_1-8 aliphatic, C_5-8 alicyclic, or C_6-10 aromatic group having 0-5 heteroatoms, and epoxy succinic acid;

(b) allowing the reaction mixture to react at a pH of greater than about 8 and at a temperature of between about 0 and 35°

C., for a time period sufficient to either react or hydrolyze substantially all of said coupling agent and said amine-modifying agent;

(c) adding to the reaction mixture of step (b) additional mono-reactive amine-modifying agent in an amount equal to at least about 50 moles of modifying agent per mole of native collagen; and

(d) allowing the reaction mixture of step (c) to react at a pH of greater than about 8 and at a temperature of between 0 and 35°

C., for a period of time sufficient to either react or hydrolyze substantially all of said modifying agent.

19. A method of making a chemically-modified collagen compound comprising the steps of:

(a) adding to an aqueous solution of at least about 0.05 percent by weight native collagen a mono-reactive amine-modifying agent in an amount equal to at least about 25 moles of amine-modifying agent per mole of native collagen, said amine-modifying agent being selected from groups of the formula

space="preserve" listing-type="equation">O═

C═

N--R

wherein R is a substituted or unsubstituted C_1-8 aliphatic, C_5-8 alicyclic, or C_6-10 aromatic group having 0-5 heteroatoms, and epoxy succinic acid;

(b) allowing the reaction mixture of step (a) to react at a pH of greater than about 8 and at a temperature of about 0 to 35°

C. for a period of time sufficient to either react or hydrolyze substantially all of said amine-modifying agent;

(c) adding to the mixture produced in step (b) a coupling agent in an amount equal to about 1 to 600 moles of coupling agent selected from the group consisting of di- and tri-carboxylic acid halides, di- and tri-sulfonyl halides, di- and tri-anhydrides and di- and tri-reactive active esters, and compounds having at least two moieties selected from the group consisting of carboxylic acid halide, sulfonyl halide, anhydride and active ester; and

(d) allowing the reaction mixture of step (c) to react at a pH of greater than about 8 and at a temperature of about 0 to 35°

C. for a time period sufficient to either react or hydrolyze substantially all of said coupling agent;

(e) adding to the reaction mixture of step (d) additional amine-modifying agent in a concentration of at least about 75 moles of modifying agent per mole of native collagen; and

(f) allowing the reaction mixture of step (d) to react at a pH of greater than about 8, and at a temperature of between about 0 and 35°

C., for a period of time sufficient to either react or hydrolyze substantially all of said amine-modifying agent.