3D Printed Devices for Improving Cell Culture and Analytical Measurements

The use of microfluidics for improving analytical measurements and cell culture mimics is well established. Most of the work in this area has involved devices fabricated with traditional lithography and work with cells in these devices has been primarily on 2D surfaces. More recently, the use of 3D printing for creating microfluidic devices has emerged to create devices that can be printed on-demand. Concurrently, the field of 3D cell culture on extracellular matrix mimics has been shown to more closely mimic in vivo conditions. This presentation will describe the use of 3D printing to create robust microfluidic devices that integrate 3D cell culture and analysis, with electrochemistry being used to detect neurotransmitters/modulators in close-to-real-time. Part of this talk will focus on the methodology to print devices with integrated electrodes, incorporating a three-electrode set-up that is made possible by threading electrodes into a 3D-printed flow cell. This in-line system can be integrated with a separate mode of detection downstream from the electrochemical flow cell by addition of a mixing T for introduction of reagents for chemiluminescent detection of ATP. Additionally, culturing cells directly on 3D printed materials is an issue that has not been extensively studied. We will detail recent results from studies designed to understand the effect of different cleaning methodologies on the culture of cells, including methods to minimize leaching of uncured materials into the cell media. The ability to use these devices to integrate 3D culture on collagen scaffolds will be described, with approaches to integrate transwell-based TEER measurements for flow-based culture studies. Finally, work towards developing devices for microchip electrophoresis with electrochemical detection will be discussed, with channel dimensions under 50 microns with electrodes being integrated during the print process.