3D Printed Magnet‐Infused Origami Platform for 3D Cell Culture Assessments

Abstract 3D printed platforms have diverse possible applications in cell‐based assays, creating biomimetic tissue or organ microenvironments, delineating cell‐to‐cell, cell‐to‐matrix, or cell‐to‐local microenvironment interactions, and investigating drug discovery. Existing engineering techniques limit physiologically relevant 3D cell proliferation and spatiotemporal organization of cells. Herein, a facile fabrication strategy is proposed for magnetically controllable, shape‐morphing, superparamagnetic 3D iron oxide nanoparticle/cellulose acetate scaffolds produced via origami‐inspired 3D printing technology. The additional dimensionality allows the creation of highly customizable 3D in vitro magnetoactive cell culture platforms in which cells can experience gravity with uniform surface morphology, favorable long‐term biodegradability, and low iron ion release that can be actuated numerous times. Leveraging this platform's properties, the spatial and temporal proliferation of Saccharomyces cerevisiae cells are demonstrated, enabling pre‐ and post‐folding dynamic regulation of cellular behaviors at a local level. It is further demonstrated that the viability of the seeded NIH/3T3 fibroblasts remains > 94% and spreads and proliferates within the scaffold channels over a period of 7 d in culture. Therefore, this transformative cell culture assessment could provide alternative directions to revolutionize the 3D cell culture platform to monitor cellular responses to drugs, compounds, and external stimuli and advance personalized treatments.