Microneedle device for transport of molecules across tissue

• US 6,503,231 B1
• Filed: 06/10/1998
• Issued: 01/07/2003
• Est. Priority Date: 06/10/1998
• Status: Expired due to Term

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia), Valeritas, LLC
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Henry, Sebastien, Prausnitz, Mark R., Allen, Mark G., McAllister, Devin V.
• Primary Examiner(s): NGUYEN, ANH TUAN TUONG
• Application Number:
  US09/095,221
• Time in Patent Office: 1,672 Days
• Field of Search: 935/53, 604/20, 604/22, 604/35, 604/46, 604/501, 604/506, 604/181, 604/183, 604/239, 604/261, 604/890.1, 604/272, 604/191, 604/186, 347/47, 298/900.1, 424/449, 424/483, 216/75, 216/100, 216/102
• US Class Current: 604/272
• 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 for transport of therapeutic and diagnostic materials and/or energy across tissue barriers, and methods for manufacturing the devices, are provided. The microneedles are hollow and/or porous and have diameters between about 10 nm and 1 mm. The microneedle devices permit drug delivery (or removal or sensing of body fluids) at clinically relevant rates across skin or other tissue barriers, without damage, pain, or irritation to the tissue. Microfabrication techniques are used to cost-effectively produce arrays of microneedles from metals, silicon, silicon dioxide, ceramic, and polymeric materials. Methods are provided for making porous or hollow microneedles.

Claims

1. A device for transport of material or energy across biological barriers comprising:

a plurality of hollow microneedles having a length between 100 μ

m and 1 mm, and

a substrate to which the microneedles are attached or integrally formed, the microneedles extending at an angle from the substrate,

wherein the microneedles are made by a microfabrication technique from a material selected from the group consisting of silicon, silicon dioxide, metals, ceramics, and combinations thereof, and

wherein each microneedle has a shaft, a portion of which comprises one or more substantially annular bores or channels therethrough and which has a width between about 1 μ

m and 100 μ

m.

2. The device of claim 1 wherein the microfabrication technique is a micromachining technique selected from the group consisting of lithography, plasma etching, wet chemical etching, dry etching, thermal oxidation of silicon, electroplating, electroless plating, boron diffusion, phosphorus diffusion, arsenic diffusion, antimony diffusion, ion implantation, film deposition, sputtering, chemical vapor deposition, epitaxy, chemical anodization, electrochemical anodization, and combinations thereof.

3. The device of claim 1 wherein the width of the entire shaft of the microneedles is between about 1 μ

m and 100 μ

m.

4. The device of claim 1 wherein the length of the microneedles are between about 100 μ

m and 500 μ

m.

5. The device of claim 1 wherein the microneedles are in communication with a reservoir.

6. The device of claim 1 wherein the material comprises a metal.

7. The device of claim 1 wherein one or more of the microneedles each comprise a base end which tapers to a sharp tip end, wherein the width of the base end is between about 10 μ

m and 100 μ

m.

8. The device of claim 1 wherein the angle is about 90°

.

9. The device of claim 6 wherein the material consists essentially of metal.

10. The device of claim 1, wherein the substrate comprises a metal.

11. The device of claim 5, wherein the reservoir contains a drug.

12. The device of claim 11, wherein the drug comprises insulin.