Electrospun nanofibers and membrane

Abstract

The present invention relates to a process for preparing nanofibers and nanofiber membranes and to the nanofibers and nanofiber membranes obtainable by such process.

Claims

1. A process for the preparation of an insoluble glycosaminoglycan-containing nanofiber membrane, comprising: a) providing a water solution containing: at least a glycosaminoglycan in an amount from 0,01% to 5,00%; at least a polymer chosen in the group consisting of hydrophilic cellulose derivatives; pullulan; mixtures of pullulan and chitosan; mixtures of pullulan and hydrophilic cellulose derivatives; and gelatins, said polymer being in an amount of 1% to 30%; acetic acid in amount of at least 20%; and a polycarboxylic acid in an amount of 0,1% to 5,00%; all percentages being by weight with respect to the total weight of the water solution; b) electrospinning said water solution on a collector of an electrospinning apparatus to form nanofibers; and c) crosslinking said nanofibers to obtain the insoluble glycosaminoglycan-containing nanofiber membrane, wherein the crosslinking is performed without glutaraldehyde vapors.

2. The process according to claim 1, wherein said polymer is a mixture of chitosan in amount of 1% to 4% and pullulan in amount of 7% to 15%, all percentages being by weight with respect to the total weight of the water solution.

3. The process according to claim 1, wherein said polymer is gelatin type B in an amount of 15% to 25%, all percentages being by weight with respect to the total weight of the water solution.

4. The process according to claim 1, wherein said glycosaminoglycan is in an amount of 0.5±0.05%, percentages being by weight with respect to the total weight of the water solution.

5. The process according to claim 1, wherein said water solution further comprises antimicrobial agents.

6. The process according to claim 1, wherein said crosslinking comprises heating said nanofibers at a temperature of 100° C. to 170° C. for a period of at least 15 minutes.

7. The process according to claim 6, wherein said crosslinking comprises heating of said nanofibers at a temperature of 150±1° C. for a period of at least 15 minutes.

8. The process according to claim 1, wherein said polycarboxylic acid is citric acid or glutamic acid.

9. The process according to claim 8, wherein said water solution comprises citric acid in amount of 2% to 3%, all percentages being by weight with respect to the total weight of the solution.

10. The process according to claim 9, wherein said glycosaminoglycan is selected in the group consisting of chondroitin sulfate, hyaluronic acid and mixtures thereof.

11. The process according to claim 1, wherein the crosslinking is performed without a toxic crosslinking agent.

Description

EXAMPLES

(1) The following compositions were prepared.

(2) Composition 1: Chitosan base (deacetylation degree 98% ChitoClear low molecular weight 251000 Da, Primex, N) 2.5% w/w; Pullulan (food grade, Hayashibara, J) 10%. Citric acid 2.5% w/w

(3) All the components were dissolved in acetic acid aqueous solution at 45% w/w.

(4) Composition 2 Chondroitin sulfate (100 EP, Bioiberica) 0.5% w/w. Chitosan base (deacetylation degree 98% ChitoClear low molecular weight 251000 Da, Primex, N) 2.5% w/w; Pullulan (food grade, Hayashibara, J) 10%. Citric acid 2.5% w/w

(5) All the components were dissolved in acetic acid aqueous solution at 45% w/w.

(6) Composition 3 Hyaluronic sodium salt (intraocular, low molecular weight, Bioiberica) 0.5% w/w. Chitosan base (deacetylation degree 98% ChitoClear low molecular weight 251000 Da, Primex, N) 2.5% w/w; Pullulan (food grade, Hayashibara, J) 10%. Citric acid 2.5% w/w

(7) All the components were dissolved in acetic acid aqueous solution at 45% w/w.

(8) Composition 4: Chondroitin sulfate (100 EP, Bioiberica) 0.5% w/w. Pullulan (food grade, Hayashibara, J) 10%. Citric acid 2.5% w/w

(9) All the components were dissolved in acetic acid aqueous solution at 45% w/w.

(10) Composition 5 Hyaluronic sodium salt (intraocular, low molecular weight, Bioiberica) Pullulan (food grade, Hayashibara, J) 10%. Citric acid 2.5% w/w

(11) All the components were dissolved in acetic acid aqueous solution at 45% w/w.

(12) Composition 6: Chondroitin sulfate (100 EP, Bioiberica) 0.5% w/w. Gelatin B 10%. Citric acid 2.5% w/w

(13) All the components were dissolved in acetic acid aqueous solution at 45% w/w.

(14) Composition 7: Hyaluronic sodium salt (intraocular, low molecular weight, Bioiberica) Gelatin B 10%. Citric acid 2.5% w/w

(15) All the components were dissolved in acetic acid aqueous solution at 37.5% or 45% w/w.

(16) The so obtained compositions 1, 2, 3, 4 were electrospun, separately from each other, by using an eletrospinning apparatus equipped with a high voltage DC (direct current) source (40 kV), a 10 ml syringe with luer-lock connections to a metallic tip, a volumetric pump (Razel R99-E) and a Plexiglass® collector coated with aluminum foil for random collection and a rotating drum for aligned nanofibers. The so obtained nanofibers were subjected to thermal treatment at 150° C. for 1 h to obtain insoluble membranes.

(17) In the attached figures:

(18) FIG. 1 shows SEM (Scanning Electron Microscopy) images of nanofibrous membranes obtained from a) composition 1 b) composition 2; and c) composition 3.

(19) FIG. 2 shows CLSM (Confocal Laser Scanning Microscopy) images of fibroblasts grown on the membranes of FIG. 1 after 7 days of growth;

(20) FIG. 3 shows SEM (Scanning Electron Microscopy) images of fibroblasts grown on the membranes of FIG. 1 after 7 days of growth; and

(21) FIG. 4 shows histology of intact skin section 0) and skin sections after 18 days of treatment with the membranes obtained from a) composition 1 b) composition 2; and c) composition 3 and d) saline solution as negative control.