Microneedle arrays and methods for fabricating microneedle arrays

• US 10,525,244 B2
• Filed: 09/28/2017
• Issued: 01/07/2020
• Est. Priority Date: 09/28/2017
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Reitz, James A., Russell, Raymond M., Cannistraci, Anthony C., Pavell, David
• Primary Examiner(s): Mendez, Manuel A
• Application Number:
  US15/719,353
• Publication Number:
  US 20190091455A1
• Time in Patent Office: 831 Days
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/685 Microneedles
• CPC Class Codes: A61M 2037/0023 Drug applicators using microneedles
• CPC Class Codes: A61M 2037/0053 Methods for producing microneedles
• CPC Class Codes: A61M 37/0015 by using microneedles
• CPC Class Codes: B21D 17/02 by pressing grooving or notching of bolts, studs, or the like B21K1/54
• CPC Class Codes: B21D 22/02 Stamping using rigid devices or tools
• CPC Class Codes: B21D 22/04 for dimpling combined with perforating B21D28/24

Abstract

Microneedle arrays, methods for fabricating microneedle arrays, medical devices, and methods for operating medical devices are provided. A method for fabricating a microneedle array includes providing a sheet blank of material. Further, the method includes stamping the sheet blank of material with a progression of dies, wherein the material is displaced into the microneedle array. A medical device includes a microneedle array, a base member having a first surface supporting the microneedle array and a second surface, and a flexible wall enclosing a chamber between the flexible wall and the second surface of the base member. The flexible wall is biased toward an extended configuration enclosing a first volume in the chamber. Further, the flexible wall is movable to a depressed configuration enclosing a second volume in the chamber less than the first volume.

Claims

1. A method for fabricating a microneedle array, the method comprising:

providing a sheet blank of material having a first surface and a second surface opposite the first surface; and

stamping the sheet blank of material with a progression of dies to displace the material into a plurality of microneedles forming the microneedle array, wherein each microneedle extends away from and is solid from the first surface to a tip.

2. The method of claim 1 further comprising, after stamping the sheet blank of material with the progression of dies to displace the material into the plurality of microneedles forming the microneedle array, drilling a hole through a selected microneedle in the microneedle array.

3. The method of claim 1 further comprising, after stamping the sheet blank of material with the progression of dies to displace the material into the plurality of microneedles forming the microneedle array, drilling a hole into a selected microneedle in the microneedle array via electrical discharge machining (EDM).

4. The method of claim 1 wherein, after stamping the sheet blank of material with the progression of dies to displace the material into the plurality of microneedles forming the microneedle array, the second surface of the blank of material is continuously planar and uninterrupted.

5. The method of claim 1 wherein during and after stamping the sheet blank of material with the progression of dies to displace the material into the plurality of microneedles forming the microneedle array, the second surface of the sheet blank of material is located in a single plane.

6. A method for fabricating a microneedle array, the method comprising:

providing a sheet blank of material;

stamping the sheet blank of material with a progression of dies to displace the material into a plurality of microneedles forming the microneedle array; and

cutting the sheet blank of material into a carrier strip and a microneedle array region connected to the carrier strip, wherein stamping the sheet blank of material with the progression of dies comprises stamping the microneedle array region with the progression of dies.

7. The method of claim 6 further comprising separating the microneedle array region from the carrier strip after stamping the microneedle array region to displace the material into the microneedle array.

8. The method of claim 6 further comprising, after stamping the sheet blank of material with the progression of dies to displace the material into the plurality of microneedles forming the microneedle array, piercing the microneedle array region to form a center hole therethrough.

9. The method of claim 6 further comprising, after stamping the sheet blank of material with the progression of dies to displace the material into the plurality of microneedles forming the microneedle array, piercing the microneedle array region to form a center hole and radially-spaced holes therethrough.

10. The method of claim 6 further comprising, after stamping the sheet blank of material with the progression of dies to displace the material into the plurality of microneedles forming the microneedle array, perforating the sheet blank of material.

11. A method for fabricating a deep drawn microneedle array, the method comprising the steps of:

providing a sheet blank of material; and

drawing the sheet blank of material to form the microneedle array comprising microneedles extending up from an upper surface of a base member, wherein the base member has a thickness from the upper surface to a bottom surface of the base member, wherein the height of the microneedles above the upper surface of the base member is greater than the thickness of the base member, and wherein each microneedle is voidless from the bottom surface of base member to a tip.

12. The method of claim 11 further comprising, after drawing the sheet blank of material to form the microneedle array, drilling a hole into a selected microneedle in the microneedle array, wherein the hole extends from the bottom surface of the base member to a location on a surface of the selected microneedle between the tip of the selected microneedle and the upper surface of the base member.

13. The method of claim 11 further comprising, after drawing the sheet blank of material to form the microneedle array, drilling a hole into a selected microneedle in the microneedle array via electrical discharge machining (EDM), wherein the hole extends from the bottom surface of the base member to a location on a surface of the selected microneedle between the tip of the selected microneedle and the upper surface of the base member.

14. The method of claim 11 further comprising cutting the sheet blank of material into a carrier strip and a microneedle array region connected to the carrier strip, wherein drawing the sheet blank of material to form the microneedle array comprises drawing the microneedle array region to form the microneedle array.

15. The method of claim 14 further comprising separating the microneedle array region from the carrier strip after reverse drawing the sheet blank of material to form the microneedle array.

16. The method of claim 14 further comprising piercing the microneedle array region to form a center hole and radially-spaced holes therethrough.

17. The method of claim 14 further comprising perforating the microneedle array region.

18. The method of claim 11 wherein the material is titanium.

19. The method of claim 11 wherein:

providing the sheet blank of material comprises providing the sheet blank of material with a first surface and a second surface;

drawing the sheet blank of material to form the microneedle array comprises drawing portions of the first surface of the sheet blank of material upward while the second surface of the sheet blank of material remains planar.

20. The method of claim 11 wherein during and after drawing the sheet blank of material to form the microneedle array, the bottom surface of the base member is located in a single plane.