Evaluation of fused deposition modeling (FDM)-printed devices for microfluidic-based cell culture studies.

In this paper, we undertook an in-depth investigation of the parameters that can be optimized to create FDM-based devices (both static and fluidic) that are leak-free and can be used for cell culture. Two different types of FDM printers (Stratasys Fortus 250mc and Bambu Lab P1S/X1-carbon) were utilized and devices were printed with a polystyrene filament, since this polymer is commonly used to make cell culture flasks. Stratasys-printed devices were made leak-free by increasing the negative "air gap" values to offset the toolpath, which significantly minimized voids between layers. Bambu Lab-based devices exhibited no leakage when printed with the ironing variable enabled. These parameters were optimized based on the design (static vs. fluidic), and the final devices were able to withstand leakage when subjected to flow experiments. It was found that these devices led to the successful culture of bovine pulmonary artery endothelial cells and Madin-Darby canine kidney cells, and a comparison was made to culturing these cells on a PolyJet-based device (printed with VeroClear material). NMR analysis was employed to determine if any potential leachates of polystyrene resulted after printing of the devices. Finally, fiber scaffolds were integrated into devices to mimic extracellular matrix (ECM) and to demonstrate the ability to perform cell culture under flow conditions in such devices. It is clear that with the developed settings, robust fluidic devices for cell culture can be created and used for the successful culture of endothelial and epithelial cells.