Method and apparatus for coating skin piercing microprojections

• US 20050084604A1
• Filed: 11/09/2004
• Published: 04/21/2005
• Est. Priority Date: 03/16/2001
• Status: Active Grant

• Current Assignee: ALZA Corporation (Johnson & Johnson)
• Original Assignee: ALZA Corporation (Johnson & Johnson)
• Inventors: Trautman, Joseph C., Cormier, Michel J.N., Wright, Cedric T.
• Granted Patent: US 7,435,299 B2
• Time in Patent Office: Days
• US Class Current: 427/2.100
• CPC Class Codes: A61B 17/205 Vaccinating by means of needles or other puncturing devices
• CPC Class Codes: A61K 9/0021 Intradermal administration, e.g. through microneedle arrays, needleless injectors mechanical aspects A61M
• CPC Class Codes: A61M 2037/0046 Solid microneedles
• CPC Class Codes: A61M 2037/0053 Methods for producing microneedles
• CPC Class Codes: A61M 37/0015 by using microneedles
• CPC Class Codes: B05D 1/18 performed by dipping
• CPC Class Codes: B05D 1/28 performed by transfer from the surfaces of elements carrying the liquid or other fluent material, e.g. brushes, pads, rollers

Abstract

An apparatus and method are provided for selectively applying an agent-containing liquid coating to extremely tiny skin piercing microprojections (10). The coating solution is applied to the skin piercing microprojections (10) using a coating technique which selectively coats only the skin piercing microprojections (10) and not the substrate (12) from which the microprojections (10) extend, and then dried. The coating method includes providing an agent-containing coating liquid and conveying the liquid to a liquid holding surface having a coating transfer region. The depth of the coating liquid at the coating transfer region is precisely controlled. The microprojections are then immersed to a predetermined level in the coating liquid. The liquid that coats the microprojections (10) is then dried to form a solid agent-containing coating on the microprojections (10).

Claims

1-13. -13. (canceled)

14. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating the substrate, comprising:

a rotatable member with a liquid holding surface, said liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region.

15. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a rotatable member with a curved liquid holding surface, said curved liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region.

16. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a liquid holding surface having a coating transfer region, said liquid holding surface being an outer surface of a rotatable cylindrically-shaped roller;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region.

17. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a liquid holding surface having a coating transfer region, said liquid holding surface being an outer surface of a rotatable cylindrically-shaped roller;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said coating liquid conveyor comprises rotating said roller through a bath of said coating liquid.

18. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a liquid holding surface having a coating transfer region, said liquid holding surface being an outer surface of a rotatable cylindrically-shaped roller;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller comprising a doctor blade for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said coating liquid conveyor comprises rotating said roller through a bath of said coating liquid.

19. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a liquid holding surface having a coating transfer region, said liquid holding surface being an outer surface of a rotatable cylindrically-shaped roller;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said coating liquid conveyor comprises rotating said roller through a bath of said coating liquid, wherein said coating liquid depth controller comprises a second roller, substantially parallel with said liquid holding surface roller and spaced a predetermined distance therefrom and forming a nip therebetween.

20. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a liquid holding surface having a coating transfer region, said liquid holding surface being an outer surface of a rotatable cylindrically-shaped roller;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said coating liquid conveyor comprises rotating said roller through a bath of said coating liquid, wherein said coating liquid depth controller comprises a second roller, substantially parallel with said liquid holding surface roller and spaced a predetermined distance therefrom and forming a nip therebetween, and wherein said two rollers rotate in the same rotational direction.

21. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a liquid holding surface having a coating transfer region, said liquid holding surface being an outer surface of a rotatable cylindrically-shaped roller;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth;

and a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said coating liquid conveyor comprises rotating said roller through a bath of said coating liquid, wherein said coating liquid depth controller comprises a second roller, substantially parallel with said liquid holding surface and spaced a predetermined distance therefrom and forming a nip therebetween, including a doctor blade wiping a surface of said second roller upstream of said nip.

22-26. -26. (canceled)

27. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a rotatable member with a liquid holding surface, said liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said substrate conveyor comprises a track which is adjustably positionable to a predetermined distance from said coating transfer region and a substrate holding sled which runs along said track.

28. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a rotatable member with a liquid holding surface, said liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, including a continuous substrate conveyor for continuously conveying a series of said substrates and microprojections through said coating liquid.

29. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a rotatable member with a liquid holding surface, said liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, including a continuous substrate conveyor for continuously conveying a series of said substrates and microprojections through said coating liquid, wherein said continuous substrate conveyor comprises a substrate supply roll and a substrate take-up roll.

30. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a rotatable member with a liquid holding surface, said liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth; and

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, including a continuous substrate conveyor for continuously conveying a series of said substrates and microprojections through said coating liquid, wherein said continuous substrate conveyor comprises a substrate supply roll and a substrate take-up roll, further including a substrate guide for positioning said continuous substrate relative to said coating transfer region.

31. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a rotatable member with a liquid holding surface, said liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating liquid at said coating transfer region to a predetermined depth;

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said coating liquid is comprised of a liquid solvent and said agent, said coating liquid having an agent concentration; and

means for controlling said agent concentration selected from the group consisting of, a temperature controller for controlling the temperature of said coating to a level which reduces evaporative loss of said liquid solvent, a coating atmosphere controller for controlling levels of gaseous solvent in an atmosphere surrounding said coating which reduces evaporative loss of said liquid solvent, a liquid solvent infusor for infusing liquid solvent into said coating liquid at a rate which compensates for evaporative loss of said liquid solvent, and combinations thereof.

32. An apparatus for applying an agent-containing coating liquid onto a plurality of microprojections extending from a surface or edge of a substrate substantially without coating said substrate, comprising:

a rotatable member with a liquid holding surface, said liquid holding surface having a coating transfer region;

a coating liquid conveyor for providing said coating liquid at said coating transfer region;

a coating liquid depth controller for controlling the depth of said coating at said coating transfer region to a predetermined depth;

a substrate conveyor for conveying said microprojections at a predetermined level of immersion through said coating liquid at said coating transfer region, wherein said coating liquid is comprised of a liquid solvent and said agent, said coating liquid having an agent concentration; and

means for controlling said agent concentration selected from the group consisting of, a temperature controller for controlling the temperature of said coating to a level which reduces evaporative loss of said liquid solvent, a coating atmosphere controller for controlling levels of gaseous solvent in an atmosphere surrounding said coating which reduces evaporative loss of said liquid solvent, a liquid solvent infusor for infusing liquid solvent into said coating liquid at a rate which compensates for evaporative loss of said liquid solvent, and combinations thereof, and

wherein said liquid solvent comprises water, said temperature is less than about 10°

C., and said atmosphere has a relative humidity greater than about 60%.