3D Microelectrode Array for Optical and Electrical Probing of Electrogenic Cells

Abstract

Researchers at the University of Central Florida have developed methods for microfabricating and assembling three-dimensional microelectrode arrays (3D MEAs) based on a glass-stainless steel platform. The technology uses non-traditional “makerspace microfabrication” techniques that enable the cost-effective fabrication of a device using biocompatible materials.

3D MEAs provide signal acquisition for 3D cell cultures, making them superior to 2D arrays, which provide planar cell cultures. However, 3D MEAs are more expensive and harder to fabricate. The UCF fabrication technology, however, is simple in its design and uses inexpensive components (stainless steel, glass, conductive resins) and materials. It also combines electrical and optical probing capabilities and can be scaled appropriately for more extensive and customizable array configurations.

Technical Details

The cost-effective UCF technology comprises non-traditional “makerspace microfabrication” techniques using various biocompatible materials to produce 3D MEAs rapidly and efficiently. The 3D MEAs may include a substrate body (for example, a chip), microneedles, traces, and a well for transferring electrical signals from one side of the substrate body to the other side of the body. Included are methods for using 3D MEAs to grow electrogenic cells and obtain electrophysiological signals. Additionally, the researchers developed a unique interconnect interface using 3D printing and conductive ink casting. The interconnect transitions the electrical contact from the topside of the glass chip to the bottom side of the device, exhibiting high electrical conductivity and demonstrating its effectiveness as an interconnect for a biological microdevice.

In one example application, stainless steel electrodes are planar laser micromachined and transitioned out-of-plane to have a 3D configuration of 400 µm high and 300 µm wide. The 2D to 3D transition angles are consistently perpendicular to the micromachining plane. Methods include bonding the laser micromachined 3D stainless steel onto a glass die and routing metal traces to the edge of the chip. With the glass substrate, the device can optically and electrically probe electrogenic cells to measure their electrophysiological activities. Confined precision drop-casting (CPDC) of polydimethylsiloxane (PDMS) defines uniform insulation for the 3D MEA.

Partnering Opportutnity

The research team is looking for partners to develop the technology further for commercialization.

Stage of Development

Prototype available.

Benefit

Market Application

Publications

Makerspace microfabrication of a stainless steel 3D microneedle electrode array (3D MEA) on a glass substrate for simultaneous optical and electrical probing of electrogenic cells, RSC Adv., 2020,10, 41577-41587, https://doi.org/10.1039/D0RA06070D.