CPC A61L 27/3604 (2013.01) [A61F 2/02 (2013.01); A61L 27/227 (2013.01); A61L 27/54 (2013.01); A61L 2300/406 (2013.01); A61L 2300/414 (2013.01); A61L 2400/12 (2013.01)] | 12 Claims |
1. An implantable medical device comprising:
a hybrid structure comprising coupled microfibers and nanofibers of silk fibroin, said hybrid structure obtained according to the process comprising:
a) preparing of one or more parts made of microfibrous fibroin;
b) preparing of one or more parts made of nanofibrous fibroin;
c) treating of said one or more parts of nanofibrous fibroin and of said one or more parts of microfibrous fibroin, separately or after coupling, with a solvent for fibroin and/or with a solution comprising fibroin dissolved in the solvent;
c′) if in step c) the nanofibrous and microfibrous parts have been treated separately with a solvent for fibroin and/or with a solution comprising fibroin dissolved in a solvent, coupling of said parts;
d) consolidating the hybrid microfibrous/nanofibrous structure obtained in step c) or in step c′) by thermal treatment at a temperature between 10° C. and 150° C., for a time between 1 minute and 24 hours;
e) removing the solvent by washing with water or a water-alcohol mixture at a temperature between 10° C. and 100° C., or by evaporation at a temperature between 10° C. and 100° C.,
wherein the solvent for fibroin or the solvent of the solution comprising fibroin used in step c) is selected from:
(i) formic acid, 1,1,1,3,3,3-hexafluoro-2-propanol, trifluoroacetic acid, hexafluoroacetone, N-methylmorpholine N-oxide, ionic liquids, and mixtures thereof, wherein said solvents are pure or in mixture with water;
(ii) calcium chloride-ethanol-water mixtures, calcium nitrate-methanol-water mixtures, aqueous solutions of lithium salts and;
(iii) mixtures among the solvents of (i) and (ii).
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