3D-Printed Impedance Micropump for Continuous Perfusion of the Sample and Nutrient Medium Integrated with a Liver-On-Chip Prototype.

In recent decades, organ-on-chip devices have gained substantial interest as an alternative for studying the pathophysiological processes relevant to drug screening. Micropumps are being utilized to simulate the in vivo physiological fluid flow more realistically in these organ-on-chip devices. Micropumps play a crucial role in pumping, perfusion, and circulation of fluids in various microdevices such as on-chip PCR, DNA microarrays, miniature bioreactor cell separation, and lab-on-chip biosensing platforms. With the rapid growth in technology, efficient pumping for proper circulation of media and nutrients has become imperative. In this study, we have described the design and development of an open-source impedance micropump for continuous perfusion of nutrient medium in a liver-on-chip prototype. This micropump is controlled via an integrated microcontroller board, with an observed flow rate ranging from 0.2 to 2 mL/min. Google Sketchup 2020 and DLP 3D printing were used to fabricate small precise parts of the impedance micropump. The flow rate was measured to characterize the actuating performance of the micropump. The poly-dimethyl siloxane-based liver-on-chip prototype has been fabricated using a soft photolithography procedure. Further, a study of continuous perfusion of culture medium through the liver-on-chip containing the Hepg2 cell line was successfully performed by integrating it with the impedance micropump. Hoechst staining and Alamar Blue observed cell viability to confirm the healthy cell growth inside the liver-on-chip microfluidic chip. The compactness of the overall setup allows it to fit in a Petri plate, eliminating chances of contamination while cell handling.