Institute of Macromolecular Chemistry

Leaching Mitigation Strategies for 3D-Printed Microfluidic Devices

Volkan Cirik
Lecture of the lecture cycle
23.5.2024 14:00, Club B

Demand for custom microfluidic devices for use in the chemical and biological sciences has led researchers to explore alternative manufacturing techniques. The use of additive manufacturing (i.e., 3D printing) has allows researchers to not only fabricate parts that are not possible via traditional processes, but to do so in a timely and cost-effective fashion. Methods based on stereolithography (SLA) allows for the fabrication of precise components having complicated microfluidic architectures, with channels having diameters on the order of 100s of microns; however, there remain concerns regarding the leaching of unreacted monomers from the component itself, which can affect the device functionality. In this study we examined how the rate of leaching from parts printed from several popular commercial resins was affected by not only the rigorousness of the post-processing technique, but the architecture of the part itself. We show that increased post-processing (including simple rinsing, exposure to UB, heat treatment, and sonication) leads to decreased leaching rates; however, no method could eliminate chemical leaching, where relatively high leachate concentrations were measured from all parts and in all solvents tested. In addition, we found that leaching from internal microchannels was much larger than that from external surfaces, where such leaching is dependent on the overall fluidic architecture (i.e., where the microchannel is) and post-processing treatments are much more limited with respect to external surfaces. Our findings underscore the crucial role of post-processing in reducing leaching and highlight the importance of microfluidic architecture in 3D-printed custom microfluidic biosensors.

The lecture is presented in English