Low-Cost, Fused Filament Fabrication-Prepared, 3D-Printed Microfluidic Devices with Modularly Integrated Electrodes for Electroanalytical Measurements

Decreasing costs, improving availability, and the introduction of new materials for 3D printing technologies have resulted in more extensive applications of 3D printing in chemical and biochemical research. Recently, 3D printing has been used to make microfluidic devices for chemical mixing, gradient generation, and sensing applications, including electrochemical sensing via flow-injection amperometry. While several reports of 3D-printed microfluidic devices have appeared, most of these rely on polyjet, multijet, or stereolithography methods that require expensive printers, costly materials, and/or special finishing and post-processing treatments. Here we show that low-cost, easy-to-prepare microfluidic devices, similar to those that have been reported using more expensive 3D printing methods, can be fabricated using a desktop 3D-printer based on inexpensive fused filament fabrication (FFF). We demonstrate that microfluidic devices with threaded openings can be prepared to enable insertion of 3-electrode fittings in the channel for electroanalytical measurements and applications such as sensing based on flow-injection amperometry. These devices feature channels designed to have width and height dimensions ≤800 μm and are semitransparent to allow visualization of the solution-filled channels. The FFF-printed devices described in this work provide a low-cost, simple alternative to the previously reported modular, 3D-printed systems for flow-injection analysis based on polyjet printing.