Multilayer medical devices having an encapsulated edge and methods thereof

1. A method of encapsulating a core layer of a multilayer wall of a medical device comprising: providing a medical device having a body defining a conduit, the body including a multilayer wall having an outer edge along at least one of a proximal end and a distal end, wherein the multilayer wall includes a core layer positioned between an inner layer and an outer layer; positioning a mold on at least one of the proximal and distal ends of the wall contacting at least one of the inner and outer layers and creating a cavity between the mold and the end of the wall along the core layer; softening at least one of the inner and outer layers positioned within the mold to flow into the cavity and cover the core layer.

2. The method of claim 1 wherein the inner layer comprises a hydrophilic material selected from the group consisting of hydrophilic polyurethanes, sodium alginates, potassium alginates, calcium alginates, carboxymethylcellulose, gelatin, polyvinyl alcohols, collagen, pectin, chitin, chitosan, poly(.alpha.-amino acids), polycaprolactone, polyvinylpyrrolidone, polyethylene oxides, polyethers, polysaccharides, polyhydroxyacrylate, polymethacrylate, dextran, xanthan, hydroxypropyl cellulose, methyl cellulose, bioabsorbable glasses, acrylates, methacrylates and combinations thereof.

3. The method of claim 1 wherein the inner layer further comprises a bioactive agent.

4. The method of claim 1 wherein the outer layer comprises a hydrophilic material selected from the group consisting of hydrophilic polyurethanes, sodium alginates, potassium alginates, calcium alginates, carboxymethylcellulose, gelatin, polyvinyl alcohols, collagen, pectin, chitin, chitosan, poly(.alpha.-amino acids), polycaprolactone, polyvinylpyrrolidone, polyethylene oxides, polyethers, polysaccharides, polyhydroxyacrylate, polymethacrylate, dextran, xanthan, hydroxypropyl cellulose, methyl cellulose, bioabsorbable glasses, acrylates, methacrylates and combinations thereof.

5. The method of claim 1 wherein the outer layer further comprises a bioactive agent.

6. The method of claim 1 wherein the core layer comprises a hydrophobic material selected from the group consisting of polypropylene, polyethylene, hydrophobic polyurethanes, silicones, silicon rubbers, siloxanes, polydimethylsiloxanes, polyvinyl chloride and combinations thereof.

7. The method of claim 1 wherein the medical device is selected from the group consisting of tracheal tubes, nasal cannulae, stents, administration tubes, duodenal tubes, rectal tubes, drainage tubes, feeding tubes, breathing tubes, intravenous tubes, suction catheters, delivery catheters, breathing circuits, connectors, and adaptors.

8. A method of encapsulating a core layer of a multilayer wall of a medical device comprising: providing a medical device having a body defining a conduit, the body including a multilayer wall having a core layer positioned between an inner layer and an outer layer; wherein the multilayer wall further includes a hole defined therein by an inner edge; positioning a mold into the hole defined within the multilayer wall contacting at least one of the inner and outer layers and creating a cavity between the mold and the inner edge of the hole in the wall along the core layer; and softening at least one of the inner and outer layers positioned within the mold to flow into the cavity and cover the core layer.

9. The method of claim 8 wherein the inner layer comprises a hydrophilic material selected from the group consisting of hydrophilic polyurethanes, sodium alginates, potassium alginates, calcium alginates, carboxymethylcellulose, gelatin, polyvinyl alcohols, collagen, pectin, chitin, chitosan, poly(.alpha.-amino acids), polycaprolactone, polyvinylpyrrolidone, polyethylene oxides, polyethers, polysaccharides, polyhydroxyacrylate, polymethacrylate, dextran, xanthan, hydroxypropyl cellulose, methyl cellulose, bioabsorbable glasses, acrylates, methacrylates and combinations thereof.

10. The method of claim 8 wherein the inner layer further comprises a bioactive agent.

11. The method of claim 8 wherein the outer layer comprises a hydrophilic material selected from the group consisting of hydrophilic polyurethanes, sodium alginates, potassium alginates, calcium alginates, carboxymethylcellulose, gelatin, polyvinyl alcohols, collagen, pectin, chitin, chitosan, poly(.alpha.-amino acids), polycaprolactone, polyvinylpyrrolidone, polyethylene oxides, polyethers, polysaccharides, polyhydroxyacrylate, polymethacrylate, dextran, xanthan, hydroxypropyl cellulose, methyl cellulose, bioabsorbable glasses, acrylates, methacrylates and combinations thereof.

12. The method of claim 8 wherein the outer layer further comprises a bioactive agent.

13. The method of claim 8 wherein the core layer comprises a hydrophobic material selected from the group consisting of polypropylene, polyethylene, hydrophobic polyurethanes, silicones, silicon rubbers, siloxanes, polydimethylsiloxanes, polyvinyl chloride and combinations thereof.

14. The method of claim 8 wherein the medical device is selected from the group consisting of tracheal tubes, nasal cannulae, stents, administration tubes, duodenal tubes, rectal tubes, drainage tubes, feeding tubes, breathing tubes, intravenous tubes, suction catheters, delivery catheters, breathing circuits, connectors, and adaptors.

15. The method of claim 1 wherein the inner and outer layers possess a melting temperature which is lower than a melting temperature of the core layer.

16. The method of claim 15 wherein the melting temperature of the inner and outer layers is different than the melting temperature of the core layer by at least 10° C.

17. The method of claim 15 wherein the melting temperature of the inner and outer layers is different than the melting temperature of the core layer by at least 20° C.

18. The method of claim 1 wherein the inner and outer layers possess a melt flow viscosity which is lower than a melt flow viscosity of the core layer.

19. The method of claim 18 wherein the melt flow viscosity of the inner and outer layers is different than the melt flow viscosity of the core layer by at least 5 g/10 mins. at a temperature of 120° C.

20. The method of claim 1 wherein the mold includes an upper flange connected to a middle flange via an upper base member, wherein the upper flange is in contact with the outer layer, the middle flange is in contact with the inner layer, and the upper base member is recessed from the core layer creating the cavity along the core layer.

21. The method of claim 20 wherein the mold further comprises a lower flange connected to the middle flange via a lower base member, wherein the lower flange is in contact with the outer layer and the lower base member is recessed from the core layer creating the cavity along the core layer.

22. The method of claim 8 wherein the inner and outer layers possess a melting temperature which is lower than a melting temperature of the core layer.

23. The method of claim 13 wherein the melting temperature of the inner and outer layers is different than the melting temperature of the core layer by at least 10° C.

24. The method of claim 13 wherein the melting temperature of the inner and outer layers is different than the melting temperature of the core layer by at least 20° C.

25. The method of claim 8 wherein the inner and outer layers possess a melt flow viscosity which is lower than a melt flow viscosity of the core layer.

26. The method of claim 25 wherein the melt flow viscosity of the inner and outer layers is different than the melt flow viscosity of the core layer by at least 5 g/10 mins. at a temperature of 120° C.

27. The method of claim 8 wherein the mold includes an upper flange connected to an upper base member and a lower flange connected to a lower base member, wherein the upper flange is in contact with the outer layer, the lower flange is in contact with the inner layer, and the upper base member and the lower base member are recessed from the core layer creating the cavity along the core layer of the inner edge.