Microneedle devices and methods of manufacture and use thereof

• US 8,708,966 B2
• Filed: 08/09/2010
• Issued: 04/29/2014
• Est. Priority Date: 06/10/1998
• Status: Expired due to Fees

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Allen, Mark G., Prausnitz, Mark R., McAllister, Devin V., Cros, Florent Paul Marcel
• Primary Examiner(s): Schmidt, Emily
• Assistant Examiner(s): Anderson, Michael J
• Application Number:
  US12/853,082
• Publication Number:
  US 20100312191A1
• Time in Patent Office: 1,359 Days
• Field of Search: 604/93.01, 604/264, 604/272
• US Class Current: 604/173
• CPC Class Codes: A61B 17/205 Vaccinating by means of needles or other puncturing devices
• CPC Class Codes: A61B 2010/008 Interstitial fluid
• CPC Class Codes: A61B 5/14514 using means for aiding extraction of interstitial fluid, e.g. microneedles or suction
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150282 for piercing elements, e.g. blade, lancet, canula, needle
• CPC Class Codes: A61B 5/150984 Microneedles or microblades
• CPC Class Codes: A61K 9/0021 Intradermal administration, e.g. through microneedle arrays, needleless injectors mechanical aspects A61M
• CPC Class Codes: A61M 2037/003 having a lumen
• CPC Class Codes: A61M 2037/0053 Methods for producing microneedles
• CPC Class Codes: A61M 37/0015 by using microneedles
• CPC Class Codes: A61N 1/303 Constructional details electrodes for external use A61N1/0428
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: B81B 2201/055 Microneedles
• CPC Class Codes: B81C 1/00111 Tips, pillars, i.e. raised structures microneedles A61M37/0015

Abstract

Microneedle devices are provided for transport of molecules across tissue barriers and for use as microflameholders. In a preferred embodiment for transport across tissue, the microneedles are formed of a biodegradable polymer. Methods of making these devices, which can include hollow and/or porous microneedles, are also provided. A preferred method for making a microneedle includes forming a micromold having sidewalls which define the outer surface of the microneedle, electroplating the sidewalls to form the hollow microneedle, and then removing the micromold from the microneedle. In a preferred method of use, the microneedle device is used to deliver material into or across a biological barrier from chambers in connection with at least one of the microneedles. The device preferably further includes a means for controlling the flow of material through the microneedles. Representative examples of these means include the use of permeable membranes, fracturable impermeable membranes, valves, and pumps.

Claims

1. A method for delivering of active agent across a biological barrier, the method comprising the steps of:

puncturing the biological barrier with a plurality of microneedles, the microneedles attached to or integrally formed with a substrate, wherein each of the microneedles is formed of a biodegradable polymer and an active agent dispersed in the biodegradable polymer of the microneedles;

delivering the active agent solely through biodegradation of the biodegradable polymer of the microneedles in the biological barrier.

2. The method of claim 1, wherein the biodegradable polymer comprises a plurality of biodegradable polymers.

3. The method of claim 2, wherein the biodegradable polymer comprises at least one of polylactides, polyglycolides, polylactide-co-glycolide, copolymers of polyethylene glycol, polyanhydrides, poly(ortho)esters, polyurethanes, poly(butric acid), poly(valeric acid), and poly(lactide-co-caprolactone).

4. The method of claim 1, wherein the biodegradable polymer comprises a biodegradable polymer and a non-biodegradable polymer.

5. The method of claim 1, wherein the biodegradation occurs by way of chemical breakdown of the biodegradable polymer.

6. The method of claim 1, wherein the biodegradation occurs by way of biodissolution of the biodegradable polymer.

7. The method of claim 1, wherein the microneedles are between 1 μ

m and 1 mm long, inclusive.

8. The method of claim 1, wherein the microneedles are between 10 μ

m and 500 μ

m long, inclusive.

9. The method of claim 1, wherein the microneedles are between 30 μ

m and 200 μ

m long, inclusive.

10. The method of claim 1, wherein the microneedles have a cross-sectional dimension between 10 nm and 1 mm, inclusive.

11. The method of claim 1, wherein the microneedles have a cross-sectional dimension between 1 μ

m and 200 μ

m, inclusive.

12. The method of claim 1, wherein the microneedles have a cross-sectional dimension between 10 μ

m and 100 μ

m, inclusive.

13. The method of claim 1, wherein the microneedles have a circular cross section with an outer diameter between 10 μ

m and 100 μ

m, inclusive.

14. The method of claim 1, wherein the substrate comprises a flexible material.

15. The method of claim 1, wherein the active agent is dispersed throughout the biodegradable polymer.

16. The method of claim 1, wherein the active agent is a drug.

17. The method of claim 16, wherein the drug comprises at least one of a protein, an enzyme, a polysaccharide, a polynucleotide, an organic compound, and an inorganic compound.

18. The method of claim 1, wherein at least one of the microneedles comprises a break site to remove the at least one of the microneedles from the substrate.

19. The method of claim 18, wherein the break site comprises a notch in the at least one of the microneedles.

20. The method of claim 18, wherein the break site is located adjacent the tip of the microneedles.