Multi-layer dressing as medical drug delivery system

• US 20030149406A1
• Filed: 02/05/2003
• Published: 08/07/2003
• Est. Priority Date: 02/07/2002
• Status: Abandoned Application

• Current Assignee: Her Majesty The Queen In Right of Canada As Represented By The Minister of National Defence, Pace University
• Original Assignee: Pace University
• Inventors: Martineau, Lucie, Shek, Pang Nin
• Application Number:
  US10/358,165
• Publication Number:
  US 20030149406A1
• Time in Patent Office: Days
• US Class Current: 604/304
• CPC Class Codes: A61K 9/7023 Transdermal patches and similar drug-containing composite devices, e.g. cataplasms galenical aspects of iontophoretic devices A61K9/0009; microneedle arrays A61K9/0021; buccal patches A61K9/006
• CPC Class Codes: A61L 15/26 Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof A61L15/225 takes precedence
• CPC Class Codes: A61L 15/44 Medicaments
• CPC Class Codes: A61L 15/60 Liquid-swellable gel-forming materials, e.g. super-absorbents
• CPC Class Codes: A61L 2300/602 Type of release, e.g. controlled, sustained, slow
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/40 comprising polyurethanes
• CPC Class Codes: B32B 5/32 at least two layers being foamed and next to each other
• CPC Class Codes: C08L 75/04 Polyurethanes

Abstract

A medicated multi-layered polyurethane foam dressing and drug delivery device with cooling properties, used in body cavities and on damaged tissues, particularly bums. The dressing may have at least one therapeutic agent dispersed into the polyurethane layers; an optional outer layer of either a hydrogel formulated from a polyurethane or an adhesive elastomeric material; an optional drug-free fluid-retaining layer and/or a drug-reservoir layer, each comprised of hydrophilic polyurethane foam; a non-adherent, drug-loaded surface-contacting layer of a polyurethane hydrogel; and an optional cover sheet, for surface dressings. An interposed liquid transfer control may be used at a layer interface. The conformable dressing shapes include cylindrical, oval, flatsheets in pre-determined sizes; and may be secured with a secondary dressing. The contact surface may be channeled to enhance fluid distribution.

Claims

25. The method of manufacturing a dressing, comprising the steps of:

a. mixing the components of the surface-contacting layer together to form a standardized aerated mixture;

b. spreading the aerated mixture onto a smooth support to form a sheet of predetermined thickness;

c. mixing the components of said drug containing layer to form a standardized aerated mixture; and

d. spreading the aerated mixture of step c) on top of the mixure of step b) before the mixture of step b) is fully cured, and allowing both layers to cure simultaneously.

26. The method as set forth in claim 25, wherein said drug in said drug reservoir layer is mixed with the components of said drug-reservoir layer, in carrying out said step c).

27. The method as set forth in claim 25, wherein said drug in said surface-contacting layer is mixed with the components of said surface-contacting layer, in carrying out said step a).

28. The method as set forth in claim 25, further including the steps of:

mixing the components of a second surface-contacting layer together to form a standardized aerated mixture; and

spreading said aerated mixture on top of said mixture of said step c).

29. The method as set forth in claim 25, wherein said drug is incorporated into said dressing after said layers have cured, by immersing the dressing in an aqueous solution containing said drug.

30. The method as set forth in claim 25, wherein said drug is absorbed under pressure into said dressing subsequent to the curing of said layers, said dressing layers being immersed in an aqueous solution containing said drug.

31. A method for manufacturing a dressing, comprising:

the steps of;

a. mixing the components of said surface-contacting layer together to form a standardized aerated mixture;

b. spreading the aerated mixture of step a) onto a smooth support to form a sheet of pre-determined thickness, and allowing the sheet to fully cure;

c. mixing the components of said drug reservoir layer to form a standardized aerated mixture;

d. spreading the aerated mixture of step c) onto a smooth support to form a sheet of pre-determined thickness, and allowing the sheet to fully cure; and

e. sealing the sheet obtained in step b) to the sheet obtained in step d).

32. The method as set forth in claim 31, wherein said sealing step e) is selected from the process group consisting of heat sealing, radio frequency welding, discontinuous adhesive, and ultrasonic welding.

33-1. A method of delivering a drug selected from a predetermined group to an internal area of damaged tissue of a patient, consisting of the step of applying a dressing as set forth in claim 1 to said area.