Fabrication of Fluidic Devices through Dissolution of 3D Printed Material in PDMS Mold

Microfluidic devices have been used in various applications such as chemical, biological, clinical, pharmaceutical, etc. This has motivated researchers to develop inexpensive, straightforward techniques to fabricate such devices. A team of four senior undergraduate students in a microfabrication course completed a project to develop a novel method for fabricating miniature fluidic devices using dissolving a common material used in 3D printing, Acrylonitrile Butadiene Styrene (ABS) in a Polydimethylsiloxane (PDMS) mold. The students performed all development steps, including ideation, literature review, calculation, design, fabrication, assembly, testing, and writing. This paper presents the results of fabricating a complex geometry fluidic design, which was used as an example to show the effectiveness of the fabrication process. The device selected in this research is a Tesla Valve with complex features. Two device designs with different features were 3D modeled and simulated using the SolidWorks Flow module before printing to ensure functionality and guide the design process. Next, the devices were 3D printed with ABS plastic, cast inside the PDMS material, and dissolved in an acetone bath, leaving flexible PDMS fluidic channels. The design performance was tested by forcing water at two different pressures through the devices, and the time to drain volume was measured. Finally, the entire water was completely drained through the devices, proving the successful fabrication of the devices.