Advances in Biomaterials for 3D Printing of Scaffolds and Tissues: Advances in Biomaterials for 3D Printing of Scaffolds and Tissues I
Sponsored by: TMS Functional Materials Division, TMS Structural Materials Division, TMS: Biomaterials Committee
Program Organizers: Changxue Xu, Texas Tech University; Jun Yin, Zhejiang University; Zhengyi Zhang, Huazhong University of Science and Technology; Yifei Jin, University of Nevada Reno
Monday 8:30 AM
February 28, 2022
Room: 201A
Location: Anaheim Convention Center
Session Chair: Changxue Xu, Texas Tech University; Kaidong Song, University of Florida
8:30 AM
Multifunctional Artificial Artery from Direct 3D Printing with Built-in Ferroelectricity and Tissue-matching Modulus for Real-time Sensing and Occlusion Monitoring: Jun Li1; 1University of Wisconsin-Madison
In this work, electric field-assisted 3D printing technology was developed to fabricate in situ-poled ferroelectric artificial arteries. The complex functional artery architecture was made by the development of a printable ferroelectric bio-composite which could be quickly polarized during printing and reshaped into devised objects. Synergistic effect from the ferroelectric potassium sodium niobate (KNN) particles and the ferroelectric polyvinylidene fluoride (PVDF) polymer matrix yielded a superb piezoelectric performance (bulk-scale d33 > 12 pC N-1). The sinusoidal architecture brought the mechanical modulus down to the same level of human blood vessels. The desired piezoelectric and mechanical properties of the 3D-printed artificial artery provided an excellent sensitivity to pressure change (0.306 mV/mmHg, R2> 0.99) within the range of human blood pressure (11.25 to 225.00 mmHg). The high pressure sensitivity and the ability to detect subtle vessel motion pattern change enabled early detection of partial occlusion (e.g., thrombosis), allowing for preventing grafts failure.
8:50 AM
Prediction of Cell Viability in Dynamic Optical Projection Stereolithography-based Bioprinting Using Machine Learning: Heqi Xu1; Qingyang Liu2; Changxue Xu1; Dazhong Wu2; 1Texas Tech University; 2University of Central Florida
Stereolithography (SLA)-based bioprinting is capable of fabricating 3D complicated structures such as vascular constructs with high printing accuracy and efficiency. However, maintaining high cell viability during SLA-based bioprinting process remains an unsolved challenge due to the cell damage induced by ultraviolet (UV) irradiation during the SLA printing process. Existing physics-based models have limitations on predicting cell viability with sufficient accuracy due to existing different complex pathways of cell damage. To address this issue, a data-driven predictive modeling approach using ensemble learning algorithm has been developed to predict cell viability under various experimental conditions in SLA-based bioprinting. A full factorial design of experiments has been conducted based on four critical process parameters including UV intensity, UV exposure time, polymer concentration, and layer thickness. The predictive model has been validated by the experimental results showing capability of predicting cell viability with high accuracy.
9:10 AM
NOW ON-DEMAND ONLY - 4D Printable Salicylic Acid Photopolymers for Sustained Drug-releasing, Shape Memory Soft Tissue Scaffolds: Andrew Weems1; 1Ohio University
3D printing pharmaceuticals offers long-term, sustained release of crucial drugs, but is limited by physical compounding and processing limitations. Here, salicylic acid is modified into a pro-drug form for incorporation in high concentrations, the role of different salicylic acid derivatives and of linker species is exploited using photoclick thiol-ene crosslinking in digital light processing (DLP) 3D printing to produce pro-drug scaffolds containing more than 50% salicylic acid. The scaffolds display tunable thermomechanical behaviors and elastomeric behaviors (elastic moduli of approximately 65 kPa), sustained release tuned through selection of the linker species with profiles ranging from 48 hours to several months, and cytocompatibility in 2D and 3D over a 2-week period using murine fibroblasts. Importantly, this material system is compatible with loading of other drugs for sequential, linear release profiles as a function composition, allowing for additional erosion control without compromising cytocompatibility, representing a distinct advance for 3D printing of pharmaceuticals.
9:30 AM
Additive Manufacturing of Natural Materials as a Multidisciplinary Approach in Engineering Education: Henry Colorado1; Mery Gomez-Marroquin2; Elkin Gutierrez3; 1Universidad de Antioquia; 2Universidad Nacional de Ingeniería; 3Universidad Antonio Nariño
This research shows results from additive manufacturing as an important strategy to produce multidisciplinary skills in engineering students. Case studies are presented with materials and mechanical engineering, and arts as well. Several animals and natural fibers from Colombia were manufactured with the fused deposition modeling (FDM) technique and evaluated in different ways, including mechanical response and didactics. Results reveal the potential of this technology in education and particularly in the motivation for learning and deep comprehension of details of nature only visible at the micro-scale.
9:50 AM
Effects of Cell Sedimentation on Droplet Formation Process and Cell Distribution during Inkjet Printing of Cell-laden Bioink: Heqi Xu1; Md Shahriar1; Jiachen Liu1; Changxue Xu1; 1Texas Tech University
During inkjet-based bioprinting, the cell-laden bioink is ejected out from a nozzle dispenser to form cell-laden droplets, which are utilized as building blocks to fabricate 3D constructs based on a layer-by-layer mechanism. The bioink used for bioprinting is composed of biological materials and living cells. During the bioprinting process, the suspended cells in the bioink sediment due to the gravitational force, which may significantly affect the printing reliability as well as the shape fidelity of the fabricated 3D constructs. This study quantifies the effects of cell sedimentation on droplet formation process and cell distribution. Specifically, cell distribution includes cell distribution within the nozzle during the printing process and cell distribution within the formed microspheres after printing. The outcomes of this study will benefit the reliable printing process and facilitate homogeneous cell distribution during the fabrication of 3D cellular constructs using inkjet-based bioprinting.
10:10 AM Break
10:30 AM
Acemannan Loaded Mg-doped 3D Printed Multifunctional Scaffolds: In Vivo and In Vitro Biological Property Evaluation: Ujjayan Majumdar1; Susmita Bose1; 1Washington State University
Calcium phosphate-based materials are a suitable choice for bone tissue engineering applications due to its compositional resemblance with natural bone. The flexible crystal structure of these materials allow doping with different transition metals, which enhances their biological and mechanical properties. In recent years, Acemannan, the active compound of aloe vera gel extract has drawn attention to the scientific community due its effects on new bone formation.. The current study aims to investigate the effects of naturally extracted Acemannan on the osteogenic, chemo-preventive and anti-bacterial properties of Mg doped 3D printed Calcium phosphate (CaP) scaffolds. This study will discuss the extraction method of Acemannan from organic aloe vera leaf, the release kinetics of Acemannan from Mg-doped 3D printed CaP scaffolds, and their in-vivo bone formation ability in rat distal femur models as a function of composition and release kinetics.
10:50 AM
Curcumin and Vitamin D3 Enhances Osteogenic and Chemopreventive Properties of 3D Printed CaP Bone Scaffolds: Yongdeok Jo1; Susmita Bose1; 1Washington State University
Bone trauma, severe infection, and tumor ablations are causes of critical-sized bone defects which fail to heal on their own. This has reinforced the need for novel multifunctional bone graft to support bone regeneration. Additive manufacturing (AM) has shown advanced bone grafts attaining high accuracy and part complexity in bone defect repair applications. Multifunctional three-dimensional (3D) printing of calcium phosphate scaffolds with natural biomolecules presents a new trend in patient-matched implants to facilitate bone healing and chemoprevention. Curcumin has attracted much interest due to its wide range of therapeutic uses for chemoprevention and osteoporosis. Vitamin D3, which is needed to absorb calcium in the body, is an essential nutrient to maintain bone health. We have fabricated the 3D printed scaffolds with designed porosity, matching trabecular bone strength. Dual drug delivery of curcumin and vitamin D3 from the scaffolds induced apoptosis in osteosarcoma cells and enhanced in vitro osteoblast cell proliferation.
11:10 AM
Influence of Strut-size and Cell-size Variations on Additively Manufactured Porous Ti6Al4V: Sushant Ciliveri1; Amit Bandyopadhyay1; 1Washington State University
Surface porosity on metal load-bearing implants has been proven to enhance osseointegration in orthopedic applications. Mechanical properties of porous metal coatings play a critical role in determining in vivo lifetime. There is a knowledge gap in measuring the shear strength of additively manufactured porous metal coatings at a porous-dense interface. This study focused our attention on evaluating pore morphology dependence and strut-size on compression, shear deformation, and in vitro response of additively manufactured porous Ti6Al4V structures. SLM-based AM technique was used to process two types of structures with honeycomb cell design with variations in cell- and strut-sizes. It was observed that compressive elastic modulus was sensitive to changes in strut-size over cell-size, and shear behavior at the porous-dense interface was more sensitive to changes in cell-size over strut-size. Our results are essential to minimize failure at the interface of porous metal coatings for load-bearing implants in orthopedic and dental applications.