3D Printing of Biomaterials and Devices: Session I
Sponsored by: ACerS Bioceramic Division
Program Organizers: Sahar Vahabzadeh, Northern Illinois University; Susmita Bose, Washington State University; Amit Bandyopadhyay, Washington State University; Mukesh Kumar, LincoTek Medical; Mangal Roy, Indian Institute of Technology - Kharagpur (IIT-Kgp)
Monday 8:00 AM
October 10, 2022
Room: 319
Location: David L. Lawrence Convention Center
Session Chair: Hongsoo Choi, Daegu-Gyeongbuk Institute of Science and Technology; Sahar Vahabzadeh, Northern Illinois University
8:00 AM Invited
3-D Printing in Regenerative Engineering: Yusuf Khan1; Cato Laurencin1; Godwin Dzidotor2; Amir Seyedsalehi2; 1University of Connecticut Health Center; 2University of Connecticut
The Connecticut Convergence Institute for Translation in Regenerative Engineering has taken a comprehensive approach to the repair and restoration of complex musculoskeletal tissues. Here we describe the role of 3D printing in the design and synthesis of complex, 3-dimensional, implantable scaffolds with precise architecture, degradability, and mechanical responsibilities. 3D printing has been a valuable tool for the synthesis of such scaffolds by allowing for the precise control over key design elements like pore diameter/porosity , strut diameter, and other aspects that require the precision afforded by 3D printing. We have also used 3D printing technology to develop unique devices designed to regenerate musculoskeletal tissues noninvasively by controlling joint mechanics, and also to improve the utility of complex preclinical injury models that mandate precise surgical procedures by 3D-printing pins for bone stabilization, external fixators for injury stability during healing, and jigs to facilitate accurate implant placement during the surgical procedure.
8:30 AM Invited
3D Printing Integrated with Controlled Delivery for In Situ Tissue Engineering of Complex and Inhomogeneous Tissues from Endogenous Stem/Progenitor Cells: Solaiman Tarafder1; Chang Lee1; 1Columbia University Medical Center
3D printing is becoming a booming technology to fabricate scaffolds for tissue engineering and regenerative medicine, benefited by customized design, tunable internal microstructure and a wide range of applicable materials. We developed a microprecise spatiotemporal delivery system embedded in three-dimensional (3D)-printed scaffolds, enabling the delivery of multiple GFs to desired locations with sustained release and high spatial resolution. In vitro, spatially controlled delivery of GFs with a prolonged release, guided formation of multi-tissue interfaces. In vivo, these scaffolds promoted recruitment of endogenous tendon progenitor cells followed by integrative healing of tendon-to-bone interface. Our findings demonstrate the potential of in situ tissue engineering of multi tissue interfaces by endogenous progenitor cells. Our micro-precise spatiotemporal delivery system embedded in 3D printing may serve as an efficient tool to regenerate complex and inhomogeneous tissues.
9:00 AM
3D Bioprinting with Engineered Living Materials for Advanced Biofabrication: Weinan Xu1; 1University of Akron
Engineered living materials (ELMs) are an emerging class of materials that combine living biological entities especially bacteria with functional soft materials. The incorporation of living bacteria provides the materials with biosensing, self-regenerative, and molecular computing capabilities. Recently, ELMs have also been used for direct ink writing-based 3D printing, which enables the fabrication of dynamic and active 3D structures for various applications. In this talk, I will discuss our recent progress on 3D printing with functional bacteria embedded in a supporting hydrogel matrix for advanced biofabrication. The bacteria can be genetically engineered to have specific functions, such as generating bacterial cellulose or reacting to external stimuli. We have demonstrated that 3D cellulose structures can be generated by in situ biosynthesis in the 3D printed template, which provides an efficient and versatile approach for tissue engineering using 3D nanoporous cellulose.
9:20 AM
Solvent Cast 3D Printing with Different Molecular Weight Polymers: Tyler French1; John Tolbert1; Lesley Chow1; 1Lehigh University
Solvent-cast 3D-printing (SCP) is a novel technique for fabricating high-resolution polymeric biomaterial scaffolds. Inks contain a polymer dissolved in a volatile solvent, which evaporates upon extrusion to leave behind a solid polymer filament. The goal of this work centers on characterizing how polymer molecular weight affects the mechanical properties of SCP scaffolds. Here, different molecular weights of poly(caprolactone) (80 kDa and 25 kDa) were co-dissolved in hexafluoroisopropanol at three respective ratios: 100:0, 90:10, and 80:20. Viscosity was measured using parallel plate rheology and matched to a set of known printing parameters. Filament diameters were measured using scanning electron microscopy images to show similar filament morphology and scaffold architectures across all inks. Tensile testing revealed that increasing 25 kDa PCL content correlated with decreasing filament stiffness. These data demonstrate how we can modify mechanical properties independently of scaffold architecture to investigate cell response to well-defined physical properties.
9:40 AM Invited
The Regulatory Roles of the Substrate Microenvironment in Cancer Progression in Tissue Engineering Scaffolds: Dinesh Katti1; Sharad Jaswandkar1; Hanmant Gaikwad1; Kalpana Katti1; 1North Dakota State University
The substrate microenvironment and mechanical cues influence cancer progression in in vitro systems. The presence of extracellular minerals modulates membrane proteins' conformation (such as integrin), resulting in signal transduction within the cells. Thus, cancer cell mechanobiology, influenced by cell-microenvironment interaction such as substrate stiffness and biochemical/topographic substrate properties, plays a vital role in cancer cell growth and metastasis. Our present AFM-based experimental study and finite element analysis-based computation study focuses on understanding the influence of physical features of the cellular environment, such as bonemimetic scaffold substrate stiffness, on the cancer cell's metastatic characteristics like cell adhesion. Our investigations on the cellular adhesion protein integrin (αVβ3) and the cellular cytoskeletal protein actin provide insight into their mechanical response, critical to cellular functions. Furthermore, the studies on integrin interaction with the nanoclay provide an insight into stem cell differentiation leading to bone tissue regeneration in scaffolds.
10:00 AM Break
10:20 AM
Effect of Sr2+ and Ca2+ ions on 3D printed Beta Tricalcium-Phosphate/Alginate Composite Scaffolds for Bone Tissue Engineering: Shebin Tharakan1; Sally Lee1; Serin Ahn1; Chris Mathew1; Michael Hadjiargyrou1; Azhar Ilyas1; 1New York Institute of Technology
Beta-Tricalcium Phosphate (β-TCP) is a bioceramic that is a Calcium Phosphate of Hydroxyapatite, a material commonly used for bone growth. While bioceramics are difficult to 3D print, when placed into composite materials they become printable. Here, we 3D printed β-TCP/Alginate composite scaffolds to evaluate the effect of Sr2+ and Ca2+ ions on their biomechanical properties (swelling, degradation, and Raman profiling). Results show that the presence of Sr2+ slowed down the degradation rate in physiological conditions, with Sr-doped scaffolds having a longer life-span and greater structural fidelity than the respective Ca-doped scaffolds. The Sr-doped scaffolds had greater overall swelling compared to the Ca-doped counterparts. The presence of β-TCP caused a decrease in swelling for Ca-doped scaffolds, likely due to the amount of volume it displaced per scaffold. Furthermore, the scaffold expansion data showed that the scaffolds enlarged up to 24 hours but saturated in size dimensions up to 7 days.
10:40 AM
Additive Manufacturing Process Simulation of Polyetherimide Porous Scaffolds for Bone Tissue Engineering Applications: Ramsha Imran1; Ans Al Rashid1; Muammer Koc1; 1Hamad Bin Khalifa University
Polymeric materials are being explored for their applications in biomedical sector owing to their biocompatibility and biodegradability. Recently, polyetherimide (PEI) has emerged as a potential biomaterial. Although several researchers are exploring PEEK for orthopedic applications, PEI material is still under-explored. Additionally, additive manufacturing techniques provide an opportunity to fabricate patient-specific porous structures required for bone tissue scaffolds. Several studies reported experimental investigations on additively manufactured scaffolds; however, utilization of numerical simulation tools for performance evaluation of these processes is still in infancy. Therefore, this study presents the performance assessment of 3D printed PEI-based porous scaffolds fabricated through the fused filament fabrication process. Numerical simulations of the FFF process were performed to evaluate the dimensional variations and process-induced defects. The results from these simulations will assist in identifying the hotspot regions for design improvements and investigate the mechanical properties of 3D printed porous scaffolds numerically.
11:00 AM Invited
Selective Artificial Neural Network by Targeted Delivery of Neuronal Cells Using Magnetically Controlled 3D Printed Microrobots: Hongsoo Choi1; 1Daegu-Gyeongbuk Institute of Science and Technology
Several in vitro neural network models have been developed to mimic the reconstruction and interconnection of neural networks and to study brain function and related diseases. Here we report a 3D magnetically actuated microrobot fabricated by 3D laser lithography based on two-photon polymerization for selective neurite alignment and neuronal connections. Using confocal immunofluorescence imaging, the aligned neurite outgrowth and synaptic connections in the neural network were measured. The microrobot, in which the rat's primary hippocampal cells were cultivated, was transmitted between two neural clusters by a magnetic field and then structurally and functionally connected to a neural network that can transmit neural activity signals. Neuronal activities were measured with a MEA system to monitor the propagation of extracellular axonal signals from the neural clusters. The proposed microrobot shows the potential for in vitro neural experiments to understand how neurons communicate in the neural network by actively connecting neural clusters.
11:30 AM Invited
Biohybrid Functional Material Design by Engineered Peptides: Candan Tamerler1; 1University of Kansas
Biohybrid materials continue to rapidly expand as they offer to combine biological functionality with synthetic materials. In biological systems, proteins are the most versatile biomacromolecules with the various functions they perform. Recognizing this, our group has been exploring peptides as the key molecular building blocks in designing functional biohybrid materials. We design peptides with different properties ranging from self-assembly to antimicrobial properties. By adapting experimental and computational approaches combined with transparent machine learning (ML) methods, we search for the peptides that present desired function. In our approach, we expanded our predictions from single function to bifunctional peptides to control their properties at the complex materials to tissue interfaces. Biohybrid materials that incorporates antimicrobial, and mineralization properties as well as bimodal imaging properties will be given as the recent examples. Biohybrid materials design provides to couple dynamic biological functions as an integral part of the resulting material system.