Impacts of Sterilization Method on Material Properties of 3D Printable Resins With Prolonged Exposure to Cell Culture Environments.

Low-cost 3D printing has become increasingly important in biomedical research, enabling rapid fabrication of custom cell culture devices, fixtures, and biohybrid robotic components. However, little is known about how common sterilization procedures and prolonged cell culture exposure impact the mechanical properties of commercially available resins. In this study, we analyzed five candidate 3D-printable resins-three rigid (Asiga DentaGUIDE, Liqcreate Bio-Med Clear, and Phrozen AquaGray 8K) and two elastomeric (Asiga DentaGUM and Formlabs Silicone 40A)-to evaluate the effects of ethanol/UV and autoclave sterilization on material properties in phosphate-buffered saline (PBS) at physiological conditions. Using stress-strain data from tensile and compressive mechanical tests, elastic moduli, ultimate tensile strength (UTS), and strain at break were compared across sterilization techniques. Results showed that sterilization significantly altered the mechanical properties of rigid resins, with Phrozen AquaGray 8K and Liqcreate Bio-Med Clear exhibiting large reductions in tensile stiffness and strength, while Asiga DentaGUIDE retained greater stability. In contrast, elastomeric resins were more robust: Asiga DentaGUM and Formlabs Silicone 40A demonstrated minimal or nonsignificant changes across sterilization methods, though post-treatment protocols influenced variability. Notably, several rigid resins also exhibited substantially lower moduli in PBS compared to manufacturer-reported values. These findings emphasize the need for experimental validation of 3D printed resin properties under intended use conditions and suggest that Asiga DentaGUIDE and Formlabs Silicone 40A are promising candidates for biohybrid applications. Overall, this work provides critical guidance for selecting sterilization-compatible materials for biomedical devices and biohybrid robotics.