3D Bioplotter Research Papers
Evaluation of a design for a three-dimensional-printed artificial bone structure
In this work, artificial bones composed of hydroxyapatite (HA)/polyacrylonitrile (PAN) and polylactic acid (PLA) were prepared as a potential replacement for natural bone. The cylindrical specimens included an auxetic system with artificial osteons. HA/PAN and PLA were used to fabricate composite filaments by fused deposition modeling three-dimensional (3D) printing, and the obtained filaments were applied to produce reentrant artificial bone materials. Scanning electron microscopy was used to analyze the scaffold morphology and functional groups. Energy-dispersive X-ray spectroscopy was used for elemental analysis. The compressive properties of the samples were studied to determine the optimal scaffolding prototype. Compressive tests were also…
Evaluation of Bioprinting Process by RSM Training
Bioprinting is one of the newest but mostly studied additive manufacturing processes of the last decade. Despite the huge amount of literature on this topic, a huge amount of aspects still have to be fully investigated. Precisely, each 3D printing process is characterized by a low stability and difficult replicability, in relation to conventional processes. For this reason, research on process control and optimization is one of the trending aspects nowadays. In this work, the Response Surface Methodology (RSM) approach is applied to 3D printing of hydrogel for biomedical applications and specifically of biocompatible hydrogels for cell-laden direct bioprinting purposes.…
Buckling Metamaterials for Extreme Vibration Damping
Damping mechanical resonances is a formidable challenge in an increasing number of applications. Many passive damping methods rely on using low stiffness, complex mechanical structures or electrical systems, which render them unfeasible in many of these applications. Herein, a new method for passive vibration damping, by allowing buckling of the primary load path in mechanical metamaterials and lattice structures, is introduced, which sets an upper limit for vibration transmission: the transmitted acceleration saturates at a maximum value in both tension and compression, no matter what the input acceleration is. This nonlinear mechanism leads to an extreme damping coefficient tanδ ≈ 0.23…
Low-density tissue scaffold imaging by synchrotron radiation propagation-based imaging computed tomography with helical acquisition mode
Visualization of low-density tissue scaffolds made from hydrogels is important yet challenging in tissue engineering and regenerative medicine (TERM). For this, synchrotron radiation propagation-based imaging computed tomography (SR-PBI-CT) has great potential, but is limited due to the ring artifacts commonly observed in SR-PBI-CT images. To address this issue, this study focuses on the integration of SR-PBI-CT and helical acquisition mode (i.e. SR-PBI-HCT) to visualize hydrogel scaffolds. The influence of key imaging parameters on the image quality of hydrogel scaffolds was investigated, including the helical pitch (p), photon energy (E) and the number of acquisition projections per rotation/revolution (Np), and, on…
Enhanced osteochondral repair with hyaline cartilage formation using an extracellular matrix-inspired natural scaffold
Osteochondral defects pose a great challenge and a satisfactory strategy for their repair has yet to be identified. In particular, poor repair could result in the generation of fibrous cartilage and subchondral bone, causing the degeneration of osteochondral tissue and eventually leading to repair failure. Herein, taking inspiration from the chemical elements inherent in the natural extracellular matrix (ECM), we proposed a novel ECM-mimicking scaffold composed of natural polysaccharides and polypeptides for osteochondral repair. By meticulously modifying natural biopolymers to form reversible guest–host and rigid covalent networks, the scaffold not only exhibited outstanding biocompatibility, cell adaptability, and biodegradability, but also…
4D Printing of Humidity-Driven Seed Inspired Soft Robots
Geraniaceae seeds represent a role model in soft robotics thanks to their ability to move autonomously across and into the soil driven by humidity changes. The secret behind their mobility and adaptivity is embodied in the hierarchical structures and anatomical features of the biological hygroscopic tissues, geometrically designed to be selectively responsive to environmental humidity. Following a bioinspired approach, the internal structure and biomechanics of Pelargonium appendiculatum (L.f.) Willd seeds are investigated to develop a model for the design of a soft robot. The authors exploit the re-shaping ability of 4D printed materials to fabricate a seed-like soft robot, according…
Hydrogel Bioinks of Alginate and Curcumin-Loaded Cellulose Ester-Based Particles for the Biofabrication of Drug-Releasing Living Tissue Analogs
3D bioprinting is a versatile technique that allows the fabrication of living tissue analogs through the layer-by-layer deposition of cell-laden biomaterials, viz. bioinks. In this work, composite alginate hydrogel-based bioinks reinforced with curcumin-loaded particles of cellulose esters (CEpCUR) and laden with human keratinocytes (HaCaT) are developed. The addition of the CEpCUR particles, with sizes of 740 ± 147 nm, improves the rheological properties of the inks, increasing their shear stress and viscosity, while preserving the recovery rate and the mechanical and viscoelastic properties of the resulting fully cross-linked hydrogels. Moreover, the presence of these particles reduces the degradation rate of…
Augmented Repair and Regeneration of Critical Size Rabbit Calvaria Defects with 3D Printed Silk Fibroin Microfibers Reinforced PCL Composite Scaffolds
Treatment of critical size defects is quite challenging, often requiring autologous bone grafts for bone regeneration. A massive volume of autologous bone is essential during this process to fill the defect leading to donor site morbidity. Although 3D printed PCL scaffolds are frequently utilised for bone correction procedures, there have been reports of delayed PCL biodegradation and inadequate bone tissue formation. To enhance the regenerative potential, in this study, silk in the form of silk fibroin microfibers are reinforced into the PCL matrix to form the composite. Two silk variations were used: Antheraea mylitta and Bombyx mori, and has been…
About the Mechanical Strength of Calcium Phosphate Cement Scaffolds
For the treatment of bone defects, biodegradable, compressive biomaterials are needed as replacements that degrade as the bone regenerates. The problem with existing materials has either been their insufficient mechanical strength or the excessive differences in their elastic modulus, leading to stress shielding and eventual failure. In this study, the compressive strength of CPC ceramics (with a layer thickness of more than 12 layers) was compared with sintered β-TCP ceramics. It was assumed that as the number of layers increased, the mechanical strength of 3D-printed scaffolds would increase toward the value of sintered ceramics. In addition, the influence of the…
Testing mesenchymal stem cells on biocompatible 3D scaffold
The composite, thermoplastic material composed of polyhydroxybutyrate (PHB) and polylactic acid (PLA) was seeded with stem cells in the experiment. Tests of the polymer were oriented towards biocompatibility in vitro using mesenchymal stem cells isolated from the chorion. PHB/PLA is a currently tested biopolymer for applications in and medicine. Using additive technology, 3D forms of scaffolds in the form of a grid were prepared, which were seeded with stem cells and cultivated in suitable conditions. After an interval of 5 days, the proliferation and viability of the mesenchymal stem cells was tested by the proliferation test. From the results, it…