Haemostatic patch and method of preparation

Patent metadata

Field	Value
Publication number	US-9750837-B2
Application number	US-201314421200-A
Country	US
Kind code	B2
Filing date	Sep 25, 2013
Priority date	Sep 25, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

The present invention relates to a haemostatic patch comprising a porous layer based on oxidized cellulose and a neutralized film based on chitosan, said film comprising a free face and a face fixed on one of the faces of the porous layer, and to the method of preparing said patch comprising the following steps: —a°) preparing a porous layer based on oxidized cellulose, —b°) preparing a film based on chitosan starting from an acidic aqueous solution of chitosan, —c°) fixing the film obtained in b°) on one face of the porous layer, —d°) neutralizing the film obtained in b°), —where step c°) can be carried out before or after step d°), characterized in that: the neutralizing step d°) comprises treatment of said film with a neutralizing composition comprising at least ethanol and ammonium hydroxide (NH 4 OH).

First claim

What is claimed is:

1. A method of preparing a haemostatic patch comprising a porous layer including oxidized cellulose and a film including neutralized chitosan, the film comprising a first free face and a second face fixed on a first face of the porous layer, comprising the following steps:
a) preparing a porous layer including oxidized cellulose,
b) preparing a film including chitosan starting from an acidic aqueous solution of chitosan,
c) fixing the film obtained in b) on a face of the porous layer,
d) neutralizing the film obtained in b), wherein step c) is carried out before or after step d) and the neutralizing step d) comprises treating the film with a neutralizing composition comprising at least ethanol and ammonium hydroxide.

2. The method according to claim 1 , wherein step d) comprises a succession of operations of contacting at least the first free face of the film with the neutralizing composition.

3. The method according to claim 1 , wherein step d) further comprises washing the first free face of the film after treating with the neutralizing composition.

4. The method according to claim 3 , wherein the washing comprises one or more operations of rinsing at least the first free face of the film with a composition comprising ethanol and water followed by a washing with water.

5. The method according to claim 1 , wherein step c) is carried out before step d).

6. The method according to claim 1 , wherein step b) comprises pouring the acidic aqueous solution of chitosan into a mold as at least one layer, and drying the at least one layer by evaporation of water from the acidic aqueous solution to obtain the film.

7. The method according to claim 6 , wherein step c) comprises depositing the face of the porous layer of oxidized cellulose on the film prior to the drying of step b) being complete, and allowing the film to dry completely to provide fixation of the porous layer on the film.

8. The method according to claim 7 , wherein step d) comprises applying the neutralizing composition to the first free face of the film and the neutralizing composition further comprises water.

9. The method according to claim 8 , wherein the neutralizing composition consists of an ethanol/water/ammonium hydroxide mixture in a proportion of 80/16/14 by weight.

10. The method according to claim 7 , wherein step d) comprises applying the neutralizing composition on the first free face of the film one or more times using a brush.

11. The method according to claim 1 , wherein step d) is carried out before step c).

12. The method according to claim 11 , wherein step b) comprises pouring the acidic aqueous solution of chitosan into a mold as at least one layer, and drying the at least one layer by evaporation of water from the acidic aqueous solution until the film is obtained and removed from the mold.

13. The method according to claim 12 , wherein step d) comprises immersing the film obtained in step b) in the neutralizing composition.

14. The method according to claim 13 , wherein the film obtained in step b) is immersed in the neutralizing composition for 30 minutes.

15. The method according to claim 13 , wherein the neutralizing composition consists of an ethanol/ammonium hydroxide mixture in a proportion of 80/20 by weight.

16. The method according to claim 13 , wherein step c) comprises fixing the film obtained at the end of step d) on the face of the porous layer of oxidized cellulose by using a glue comprising an acidic solution of chitosan.

17. The method according to claim 16 , wherein the glue is spread on the face of the porous layer and/or on the second face of the film intended to be fixed to the porous layer, and the film is fixed to the porous layer by application of the film on the face of the porous layer with pressure.

18. The method according to claim 1 , wherein the acidic aqueous solution of chitosan of step b) further comprises a plasticizer.

19. The method according to claim 18 , wherein the plasticizer comprises glycerol.

20. The method according to claim 1 , wherein the porous layer is a textile.

21. The method according to claim 1 , wherein the porous layer is a three-dimensional knitted fabric.

22. A haemostatic patch obtained by the method according to claim 1 , comprising a porous layer including oxidized cellulose and a film including chitosan fixed to one face of the porous layer, wherein the film is in a neutralized form.

Assignees

• Sofradim Production

Inventors

• Serrero Aurelie
• Montanari Suzelei

Classifications

• C08L5/08

  Chitin; Chondroitin sulfate; Hyaluronic acid; Derivatives thereof · CPC title

• B32B37/1284

  Application of adhesive · CPC title

• A61L15/44

  Medicaments · CPC title

• B32B38/162

  Cleaning · CPC title

• C08L1/04

  Oxycellulose; Hydrocellulose {, e.g. microcrystalline cellulose} · CPC title