I-Corps: 3D Printing of Microneedles for Transdermal Drug Delivery

The broader impact/commercial potential of this I-Corps project is the development of a microneedle technology for drug delivery and other applications based on 3D printing. Additive manufacturing is a promising technology that may be used for fabrication of customizable, complex, and cost-effective microneedles arrays (MNAs). MNA devices are micron-sized needles that pierce the outer layer of tissue (skin) to deliver drugs in the form of proteins, molecules, and/or peptides into the body.

MNAs are considered painless, minimally invasive devices. Currently, MNA patches developed using traditional technologies such as molding, chemical wet etching, and direct laser micromachining require advanced manufacturing facilities, have limited customizability, and lack flexibility over specific MN parameters. The proposed technology allows superior control over geometric parameters such as sub-millimeter height, tip sharpness, and high-aspect ratio.

Applications of MNA patches include drug delivery, electric stimulation, chemical biosensing, electrical biosignal recording, and neutral interfaces.

This I-Corps project is based on the development of microneedle array (MNA) devices that are micron-sized needles that pierce the outer layer of skin (epidermis) to deliver drugs into the body. The proposed technology is based on a customizable stereolithography (SLA) technique for fabricating high quality MNA devices with 10 µm - 100 µm resolution using biocompatible and biodegradable materials.

The microneedles may be fabricated with tip heights of 200 µm - 800 µm and diameters of 50 µm - 200 µm, respectively. Using this SLA advanced manufacturing technique, various MNAs such as conical-, pyramidal-, tetrahedron-, angled, honeybee structure, and arrowhead-shaped may be fabricated with high fidelity and mechanical properties. The proposed microneedle technology can bridge current treatment modalities and is amenable to scale-up for large-scale transdermal applications.

Moreover, 3D printed microneedles may be embedded with pharmaceuticals providing tunable drug release kinetics for a variety of medical treatments. These MNA patches will be designed to possess superior mechanical strength and piercing capacity for transdermal drug delivery applications in hospitals, ambulatory surgical centers, and specialty clinics.

The initial market target of this technology is diabetes diagnostics to deliver insulin and regulate glucose for Type 1 diabetes treatment. In addition, these MNAs may provide therapeutic efficiency, and safe, painless penetration through skin that may be easily adapted for other drug delivery modalities.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.