(285d) 3D Synthetic Brain: Manufacturing, Challenges, and Fundamental Studies

3D printing-based additive manufacturing technologies have been used to produce 3D synthetic brains from thermoplastic polymers that are primarily rigid. Bioprinting technologies are continuously advancing the current knowledge for in-vitro studies utilizing hydrogel-based biomaterials; yet, manufacturing complex three-dimensional (3D) shapes (e.g., miniaturized 3D brain) from soft and squishy hydrogels remains a fundamental challenge. While current studies utilizing rigid 3D brains aim for teaching, surgical planning, and training protocols, we demonstrate a subject-specific miniaturized synthetic 3D brain manufacturing for proof-of-concept studies utilizing soft and squishy biomaterial, i.e., Agarose-gel. 0.6% (w/v) and 2% (w/v) Agarose-gel shares tissue-specific mechanistic details of healthy and diseased brains that we targeted to demonstrate the utility of the manufactured 3D synthetic brain. Manufacturing 3D brains harnessing pure Agarose-gels enable molecular diffusion studies, which previously remained a gap in the literature that we overcome. Towards that goal, subject-specific magnetic resonance imaging (MRI) data were evaluated, segmented, and reconstructed to produce a volumetric STL file; then, we produced an elastomeric inverse replica mold from a rigid 3D printed brain utilizing the volumetric STL data. Pouring and gelling Agarose-gels within the inverse replica mold produce the soft and squishy brains onto which Methylene Blue was infused to investigate time-dependent molecular diffusion. Beyond molecular diffusion, a soft and squishy 3D brain from Agarose can provide platforms for other studies relevant to drug delivery, neural stimulation, neuroelectronics, and neurofluidics.