COATING METHOD

• US 20110059150A1
• Filed: 12/23/2008
• Published: 03/10/2011
• Est. Priority Date: 12/24/2007
• Status: Active Grant

• Current Assignee: Vaxxas Pty Ltd.
• Original Assignee: The University of Queensland
• Inventors: Chen, Xianfeng, Fernando, Germain, Kendall, Mark Anthony Fernance, Prow, Tarl
• Granted Patent: US 9,220,678 B2
• Time in Patent Office: Days
• US Class Current: 424/423
• CPC Class Codes: A61K 39/39 characterised by the immunostimulating additives, e.g. chemical adjuvants
• CPC Class Codes: A61K 9/0021 Intradermal administration, e.g. through microneedle arrays, needleless injectors mechanical aspects A61M
• CPC Class Codes: A61M 2037/0023 Drug applicators using microneedles
• CPC Class Codes: A61M 2037/0046 Solid microneedles
• CPC Class Codes: A61M 37/0015 by using microneedles
• CPC Class Codes: B05D 3/0466 the gas being a non-reacting gas B05D3/0406 takes precedence

Abstract

A method of coating a material onto projections provided on a patch. The method includes applying a coating solution containing the material to at least the projections and drying the coating solution to at least the projections using a gas flow.

Claims

1. A method of coating a material onto projections provided on a patch, wherein the method includes:

a) applying a coating solution containing the material to at least the projections; and

,

b) drying the coating solution using a gas flow.

2. A method according to claim 1, wherein the method includes at least one of:

a) distributing the coating solution over the projections at least in part using the gas flow; and

,

b) moving coating solution on patches to wet all projections using a gas flow, thereby coating at least part of the projections.

3. A method according to claim 1, wherein the method includes selecting one or more coating properties to thereby control the distribution of coating over the projections.

4. A method according to claim 3, wherein one or more coating properties are selected so that at least one of:

a) at least tips of the projections are coated; and

,

b) at least target sections of the projections are coated.

5. A method according to claim 3, wherein the projections are provided on a surface of the patch, and wherein the method includes selecting one or more coating properties to thereby vary at least one of:

a) an amount of coating on a surface of the patch; and

,

b) an amount of coating on the projections.

6. A method according to claim 3, wherein the coating properties include at least one of:

a) a gas flow rate;

b) one or more patch properties;

c) one or more coating solution properties; and

,

d) a drying time.

7. A method according to claim 6, wherein the patch properties include at least one of:

a) projection size;

b) projection shape;

c) projection spacing; and

,

d) one or more projection materials.

8. A method according to claim 6, wherein the coating solution properties include at least one of:

a) a surface tension; and

,

b) a viscosity.

9. A method according to claim 1, wherein the material includes at least one of:

a) nanoparticles;

b) a nucleic acid or protein;

c) an antigen, allergen, or adjuvant;

d) parasites, bacteria, viruses, or virus-like particles;

e) quantum dots, SERS tags, Raman tags or other nanobiosensors;

f) metals or metallic compounds; and

,

g) molecules, elements or compounds.

10. A method according to claim 1, wherein the coating solution includes a therapeutic agent.

11. A method according to claim 10, wherein the therapeutic agent is at least one of.

a) DNA having a concentration of between 0.01 mg/ml and 5 mg/ml;

and,

b) protein having a concentration of between 0.01 mg/ml and 50 mg/ml

12. A method according to claim 1, wherein the coating solution includes at least one of:

a) a viscosity enhancer;

b) a surfactant; and

,

c) an adjuvant.

13. A method according to claim 12, wherein the adjuvant acts as a surfactant.

14. A method according to claim 12, wherein at least one of:

a) the viscosity agent is 0% to 90% of the coating solution; and

,

b) the surfactant is 0% to 90% of the coating solution.

15. A method according to claim 12, wherein the viscosity agent is at least one of MC, CMC, gelatin, agar, and agarose.

16. A method according to claim 1, wherein the coating solution has a viscosity of between 10⁻

3 Pa·

S and 1 Pa·

S.

17. A method according to claim 16, wherein the coating solution has a viscosity of 0.01-0.06 Pa·

S

18. A method according to claim 1, wherein the coating solution has a surface tension of between 0.023 N/m and 0.073 N/m.

19. A method according to claim 18, wherein the coating solution has a surface tension of 0.03-0.04 N/m.

20. A method according to claim 1, wherein the gas flow has a gas flow rate of between 6 m/s and 10 m/s.

21. A method according to claim 1, wherein the method includes selecting a gas flow rate in accordance with gas properties.

22. A method according to claim 21, wherein the gas properties include a gas density.

23. A method according to claim 1, wherein the gas flow includes at least one of:

a) nitrogen;

b) argon;

c) air flow; and

,

d) an inert gas.

24. A method according to claim 1, wherein the gas flow is induced at least in part by extracting gas from a container containing the patch.

25. A method according to claim 1, wherein the method includes coating the projections a number of times.

26. A method according to claim 25, wherein the method includes:

a) coating the surface a first time using a first set of coating parameters; and

,

b) coating the surface at least a second time using a second set of coating parameters different to the first set of coating parameters.

27. A method according to claim 1, wherein the method includes applying between 5 and 15 μ

l of coating solution to the patch.

28. A method according to claim 1, wherein the patch has a surface area of approximately 0.16 cm².

29. A method according to any one of the claims 1, wherein the projections have a density of between 1,000-30,000 projections/cm².

30. A method according to claim 29, wherein the projections have a density of 20,000 projections/cm²

31. A method according to claim 1, wherein the projections have a length of between 10 to 400 μ

m.

32. A method according to claim 31, wherein the projections have a length of 90 μ

m

33. A method according to claim 1, wherein the projections have a radius of curvature of greater than 1 μ

m.

34. A method according to claim 33, wherein the projections have a radius of curvature greater than 5 μ

m.

35. A device according to claim 1, wherein the projections include a support section and a targeting section.

36. A device according to claim 35, wherein the targeting section has a diameter of less than at least one of:

a) 50 μ

m; and

,

b) 100 μ

m;

c) 150 μ

m; and

,

d) 400 μ

m.

37. A device according to claim 35, wherein a length for the targeting section is at least:

a) less than 50 μ

m; and

,

b) less than 100 μ

m; and

,

c) less than 300 μ

m.

38. A device according to claim 35, wherein a length for the support section is at least one of:

a) for epidermal delivery <

200 μ

m;

b) for dermal cell delivery <

1000 μ

m;

c) for delivery to basal cells in the epithelium of the mucosa 600-800 μ

m; and

,

d) for lung delivery of the order of 100 μ

m.

39. A device according to claim 35, wherein a length for the support section is at least one of:

a) for epidermal delivery greater than the thickness of the Stratum Corneum;

b) for dermal cell delivery greater than the thickness of epidermis;

c) for delivery to basal cells in the epithelium of the mucosa greater than a thickness of upper epithelium; and

,

d) for lung delivery of the order of 100 μ

m in this case.

40. A device according to claim 1, wherein the projections are solid.

41. A device according to claim 1, wherein the projections are non-porous and non-hollow.

42. A method according to claim 1, wherein the patch is at least one of:

a) hydrophobic; and

,

b) hydrophilic.

43. A method of coating a material onto projections provided on a patch, wherein the method includes:

a) applying a coating solution containing the material to at least the projections; and

,

b) distributing the coating solution over the projections at least in part using a gas flow.

44. A method according to claim 43, wherein the method further includes drying the coating solution using the gas flow.

45. (canceled)

46. A coating solution for coating a material onto projections on a patch, the coating solution including Quillaja saponins acting as a surfactant and a vaccine adjuvant.

47. A coating solution according to claim 46, wherein the Quillaj a saponins include at least one of QA, QS-21, QS-7 and one or more other purified saponin adjuvants.

48. A coating solution according to claim 46, wherein the coating solution includes an adjuvant that is an Immunostimulating complex.

49. A coating solution according to claim 48, wherein the Immunostimulating complex includes ISCOMATRIX.

50. A coating solution according to claim 46, wherein the coating solution includes at least one of:

a) a viscosity enhancer;

b) a surfactant; and

,

c) an adjuvant.

51. (canceled)

52. A coating solution for coating a material onto projections on a patch, the coating solution including nanoparticles.

53. A coating solution according to claim 52, wherein the nanoparticles are multilayered nanoparticles.

54. A coating solution according to claim 53, wherein the nanoparticles includes layers including at least one of:

a) cell targeting molecules; and

,

b) cell-entry facilitating molecules.

55. A coating solution according to claim 52, wherein the nanoparticles include one or more layers including intracellular targeting molecules.

56. (canceled)

57. A patch for use in medical procedures, the patch including a number of projections thereon, the projections having a coating applied thereto by:

(a) applying a coating solution containing the material to at least the projections; and

(b) drying the coating solution using a gas flow.

58. A method of performing a medical procedure, the method including applying a patch to a subject, the patch including a number of projections thereon, the projections having a coating applied thereto by:

(a) applying a coating solution containing the material to at least the projections; and

(b) drying the coating solution using a gas flow.

59. A method according to claim 58, wherein the method includes hydrating a surface of the subject and applying the patch to the hydrated surface.