Microneedles for minimally invasive drug delivery
US6980855B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 29, 2004 |
| Grant date | Dec 27, 2005 |
| Priority date | — |
| Expiry date | Feb 4, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB81B2201/055
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The present invention provides a microneedle incorporating a base that is broad relative to a height of the microneedle, to minimize breakage. The microneedle further includes a fluid channel and a beveled non-coring tip. Preferably arrays of such microneedles are fabricated utilizing conventional semiconductor derived micro-scale fabrication techniques. A dot pattern mask is formed on an upper surface of a silicon substrate, with each orifice of the dot pattern mask corresponding to a desired location of a microneedle. Orifices are formed that pass completely through the substrate by etching. A nitride pattern mask is formed to mask all areas in which a nitride layer is not desired. A nitride layer is then deposited on the bottom of the silicon substrate, on the walls of the orifice, and on the top of the silicon substrate around the periphery of the orifice. The nitride layer around the periphery of the orifice is offset somewhat, such that one side of the orifice has a larger nitride layer. Anisotropic etching is used to remove a substantial portion of the substrate, creating a plurality of angular, blunt, and generally pyramidal-shaped microneedles. A subsequent removal of the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.