A unique fabrication approach for microneedles using coherent porous silicon technology

The fabrication approach for microneedles using the coherent porous silicon (CPS) etching technology is presented here. Microcapillaries and microneedles form one of the components for microfluidic systems that have potential applications in drug delivery, genomics, and in micro-total-analysis systems used in detection of microbes, cells and macromolecules. This work provides a unique fabrication technology for micro-capillaries and microneedles. Porous silicon has been used in MEMS for several other applications. This is the first reported use in fabrication of microneedles. CPS technology is used to fabricate microneedle arrays with different pitch and diameters. When biological media are involved, the issue of biocompatibility arises and the use of silicon dioxide eliminates that problem because of its relative inertness in bio-medical applications.

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