ELECTRONEGATIVE FIBRE FOR USE IN THE HEALING OF WOUNDS

Abstract

A subject of the present invention is a material comprising at least one electronegative fiber having a negative charge density of between 0.01 and 5 mmol/g and a liquid absorption capacity of less than 9.5 g of physiological saline per g of fiber, for the use thereof in wound healing, and preferentially in wound cleaning. Another subject of the invention is a medical device, such as a dressing or a bandage, comprising such a material.

Claims

1. A material comprising at least one electronegative fiber having a negative charge density of between 0.01 and 5 mmol/g and a liquid absorption capacity of less than 9.5 g of physiological saline per gram of fiber, for the use thereof in wound healing.

2. The material as claimed in claim 1, wherein said material is formulated as a wound cleaning composition.

3. The material of claim 1, wherein the electronegative fiber has a negative charge density of between 0.05 and 4 mmol/g.

4. The material of claim 1, wherein the electronegative fiber is a polymer fiber, the polymer constituting the fiber being chosen from polyesters, polyamides, polyolefins and copolymers thereof, polyurethane, acrylic polymers, polyacrylates and copolymers thereof, and cellulose polymers and mixtures thereof.

5. The material of claim 1, wherein the polymer constituting the electronegative fiber is a cellulose polymer, preferably a cellulose derivative or viscose, or an acrylic polymer, preferably a copolymer of acrylonitrile and vinyl chloride.

6. The material as of claim 1, wherein the electronegative fiber is obtained either by incorporating particles having cation or polyelectrolyte exchange properties during the manufacture of said fiber, or by chemical synthesis of a polymer having suitable ionic groups.

7. The material as of claim 1, wherein the electronegative fiber is obtained by incorporating ion exchange resins bearing sulfonate groups and/or by incorporating polyelectrolytes bearing carboxylate groups into a viscose polymer matrix, or by reacting a modacrylic polymer, and in particular an acrylonitrile/vinyl chloride copolymer, with an amine having an ion exchange group.

8. The material of claim 1, wherein said material is in the form of a nonwoven, a woven or a knit.

9. The material of claim 1, wherein said material has a basis weight of greater than 75 g/m.sup.2.

10. The material of claim 1, wherein said material is partially covered with a contact layer on the face of the material which is intended to come into contact with the wound, said layer comprising openings enabling the passage of wound exudates.

11. The material of claim 1, wherein said material contains active agents promoting wound healing.

12. A medical device comprising a material of claim 1, wherein said device being a dressing or a bandage.

13. A medical device comprising a material of claim 1, wherein said device is a composite material for packing cavity wounds.

14. The material of claim 1, wherein the electronegative fiber has a negative charge density of between 0.1 and 2 mmol/g.

Description

EXAMPLE

[0123] Preparation of the Materials According to the Invention.

[0124] The following 3 materials according to the invention were prepared:

[0125] Fibers, of the Cationic Exchange Fiber model, sold by Kaneka under the name Kanecaron ion exchange fiber® were used, and they were shaped into a 97 g/m.sup.2 nonwoven material. The fibers constituting said nonwoven have a negative charge density of 1.5 mmol/g and a liquid absorption capacity of 3 g of physiological saline per gram of fiber.

[0126] Fibers, of the Cationic Exchange Fiber type model, sold by Kaneko under the name Kanecaron ion exchange fiber® were also used, and they were shaped into a 109 g/m.sup.2 nonwoven material. These fibers have a negative charge density of 1.5 mmol/g and a liquid absorption capacity of 6.3 g of physiological saline per gram of fiber.

[0127] Finally, Poseidon 3.3 dtex/40 mm fibers sold by Kelheim were used in the form of a cluster of non-transformed fibers directly resulting from the spinning process. These fibers have a negative charge density of 1,55 mmol/g and a liquid absorption capacity of 9.1 g of physiological saline per gram of fiber.

[0128] Test of In Vitro Removal of the Fibrin Matrix:

[0129] The fibrin matrices were prepared according to the protocol described by Brown in the publication “Fibroblast migration in fibrin gel matrices”, Am J. Pathol, 1993, 142: 273-283.

[0130] The components and the procedure which were used are as follows:

[0131] The following were solubilized at 37° C.: [0132] 5 ml of an aqueous solution comprising 50 mmol of HEPES (Sigma-Aldrich catalog) [0133] 15 mg of fibrinogen from human plasma (Sigma-Aldrich catalog) [0134] 5 mmol of CaCl.sub.2.

[0135] 50 μl of thrombin and 100 NIH of human plasma (Sigma-Aldrich catalog) were added to the solution thus prepared.

[0136] Everything was placed in a Petri dish and left to incubate at 37° for 24 hours.

[0137] The fibrin matrix is formed after 24 hours.

[0138] According to a first test protocol, a sample of material chosen from one of the 3 samples described above is deposited on the matrix at room temperature and then removed immediately.

[0139] According to a second test protocol, a sample of material chosen from one of the 3 samples described above is deposited on the matrix at room temperature with a weight of 500 g for 30 seconds then removed.

[0140] On removal, for each tested sample of material according to the invention, according to either one of the two protocols followed, it is observed that the fibrin had detached from the Petri dish and had transferred in a single piece to the surface of the material which was removed; this was the case for each test protocol conducted.

[0141] In parallel, comparative tests were carried out.

[0142] Thus, a nonwoven compress-type product consisting of carboxymethylcellulose fibers and sold under the name Aquacel® was tested for in vitro removal of a fibrin matrix according to the second protocol described above.

[0143] The carboxymethylcellulose fibers have a negative charge density of 1.5 mmol/g and a physiological saline absorption capacity of 24.1 g per gram of fiber.

[0144] It is observed that the fibrin matrix is not detached from the Petri dish. Moreover, when the material is placed in contact with an exudate simulator (such as a liquid solution), said material consisting of carboxymethylcellulose fibers gels, thereby becoming barely cohesive and thus making it impossible in all cases to remove said material without tearing.

[0145] Another nonwoven compress-type product, this time consisting of alginate fibers and sold under the name Algostéril®, was tested for in vitro removal of a fibrin matrix according to the second protocol described above.

[0146] The alginate fibers have a negative charge density of 5.10 mmol/g and a physiological saline absorption capacity of 12.8 g per gram of fiber.

[0147] It is observed here that the fibrin matrix is not detached from the Petri dish, even though said product is removed in a single piece. The fibrin attachment is zero.