3D Bioplotter Research Papers
Design of bioglasses/PDLLA scaffolds with responsive drug delivery in ultrasonic-assisted bone repair
Low-intensity pulsed ultrasound (LIPUS) assisted bone repair is confirmed effective in clinic. Here, a 3D-printed composite poly(DL-lactic acid)/mesoporous bioactive glass scaffold was constructed for particular use in LIPUS-assisted bone tissue engineering. The scaffolds contain dimethyloxallyl glycine (DMOG) loaded microbubbles in pores, which can be released after implanting via LIPUS stimulation. Local DMOG concentrations are modulated through ultrasound power and processing time. The rat bone marrow-derived mesenchymal stem cells (rBMSCs) on these scaffolds with ultrasound treatment show improved proliferation and early osteogenic differentiation.
Self-Adaptive MoO3−x Subnanometric Wires Incorporated Scaffolds for Osteosarcoma Therapy and Bone Regeneration
Residual tumor cells and bone tissue defects are two critical challenges in clinical osteosarcoma treatment. Herein, a subnanomedicine concept is proposed by developing a self-adaptive functional tissue engineering scaffold constructed by integrating MoO3−x subnanometric wires onto 3D printing bioactive glass scaffolds. The MoO3−x subnanometric wires are synthesized by a one-pot hydrothermal method, which aggregate in an acidic tumor microenvironment and react with hydrogen peroxide to produce reactive oxygen species for specific chemodynamic therapy. However, they can degrade rapidly under physiological conditions without causing toxicity. Moreover, self-adaptively enhanced photothermal conversion enables tumor-targeting photothermal therapy while enhancing chemodynamic therapy. Additionally, the Mo5+-Mo6+…
Optimization of 3D Printing Parameters of Polylactic-Co-Glycolic Acid-Based Biodegradable Antibacterial Materials Using Fused Deposition Modeling
A high incidence of ureteral diseases was needed to find better treatments such as implanting ureteral stents. The existing ureteral stents produced a series of complications such as bacterial infection and biofilm after implantation. The fused deposition modeling (FDM) of 3D printing biodegradable antibacterial ureteral stents had gradually become the trend of clinical treatment. But it was necessary to optimize the FDM 3D printing parameters of biodegradable bacteriostatic materials to improve the precision and performance of manufacturing. In this study, polylactic-co-glycolic acid (PLGA), polycaprolactone (PCL), and nanosilver (AgNP) were mixed by the physical blending method, and the 3D printing parameters…
4D Printed Shape Memory Polyurethane-Based Composite for Bionic Cartilage Scaffolds
Repair of articular cartilage defects is a major challenge in orthopedic surgery due to the deficient self-regeneration capability. Cartilage tissue engineering scaffolds provide a promising approach to cartilage defect repair. Proper mechanical properties, interconnected internal structure, customized shape, and minimally invasive treatment are urgent requirements for a qualified cartilage scaffold. Here, a shape memory composite used for cartilage defects is prepared by adding nanohydroxyapatite into a shape memory polyurethane matrix, exhibiting good mechanical properties and biocompatibility. Based on its rheological properties, the composite melt can be printed into 4D printed structures with high precision and quality in a simple and…
Polysiloxane Inks for Multimaterial 3d Printing of High-Permittivity Dielectric Elastomers
Dielectric elastomer transducers (DET) are promising candidates for electrically-driven soft robotics. However, the high viscosity and low yield stress of DET formulations prohibit 3D printing, the most common manufacturing method for designer soft actuators. DET inks optimized for direct ink writing (DIW) produce elastomers with high stiffness and mechanical losses, diminishing the utility of DET actuators. To address the antagonistic nature of processing and performance constraints, principles of capillary suspensions are used to engineer DIW DET inks. By blending two immiscible polysiloxane liquids with a filler, a capillary ink suspension is obtained, in which the ink rheology can be tuned…
3D Printing Process Research and Performance Tests on Sodium Alginate-Xanthan Gum-Hydroxyapatite Hybridcartilage Regenerative Scaffolds
Cartilage injury is a common occurrence in the modern world. Compared with traditional treatment methods, bio-3D printing technology features better utility in the field of cartilage repair and regeneration, but still faces great challenges. For example, there is currently no means to generate blood vessels inside the scaffolds, and there remains the question of how to improve the biocompatibility of the generated scaffolds, all of which limit the application of bio-3D printing technology in this area. The main objective of this article was to prepare sodium alginate-xanthan gum-hydroxyapatite (SA-XG-HA) porous cartilage scaffolds that can naturally degrade in the human body…
Multi-material 3D printing of piezoelectric and triboelectric integrated nanogenerators with voxel structure
Flexible and highly filled piezoelectric nanogenerators with excellent performance play an indispensable role in portable electronic devices, while the bottlenecks are hard to improve the polarization efficiency and prepare three-dimensional (3D) amplifying effect structure. Compared with other typical 3D printing technologies, direct ink writing multi-material printing (DIW-M3D), can extrude multiple viscoelastic ink materials with a wide selection of materials, which has the advantage of integrated multi-material processing. However, there are fewer reports on the use of DIW-M3D technology to print functional composite materials. Inspired from Lego block structures, we utilized DIW-M3D technology to prepare fabrications with alternating arrangements of piezoelectric…
3D-printed tungsten sheet-gyroids via reduction and sintering of extruded WO3-nanopowder inks
Additive manufacturing of objects with complex geometries from refractory metals remains very challenging. Here, we demonstrate the fabrication of tungsten sheet-gyroids via 3D ink-extrusion of WO3 nano-powder followed by hydrogen reduction and activated sintering with NiO additions, as an alternative route to beam-based additive manufacturing of tungsten and other high melting metals and alloys. The microstructure and mechanical properties of the tungsten sheet-gyroids are measured for various wall architectures and processing conditions. The original gyroid architecture, separating two equally-sized volumes, is modified to achieve double-wall gyroids (with three separate volumes) with higher relative densities. The compressive properties of these single-…
Three-Dimensionally Printed Hyperelastic Bone Scaffolds Accelerate Bone Regeneration in Critical-Size Calvarial Bone Defects
Background: Autologous bone grafts remain the gold standard for craniofacial reconstruction despite limitations of donor-site availability and morbidity. A myriad of commercial bone substitutes and allografts are available, yet no product has gained widespread use because of inferior clinical outcomes. The ideal bone substitute is both osteoconductive and osteoinductive. Craniofacial reconstruction often involves irregular three-dimensional defects, which may benefit from malleable or customizable substrates. “Hyperelastic Bone” is a three-dimensionally printed synthetic scaffold, composed of 90% by weight hydroxyapatite and 10% by weight poly(lactic-co-glycolic acid), with inherent bioactivity and porosity to allow for tissue integration. This study examines the capacity of…
A Percolation Model for Piezoresistivity in Conductor–Polymer Composites
Insulating polymer composites with conductive filler particles are attractive for sensor applications due to their large piezoresistive response. Composite samples composed of a polymer matrix filled with particles of doped semiconductor that gives a piezoresistive response that is 105 times larger than that of bulk semiconductor sensors are prepared here. The piezoresistance of such composite materials is typically described by using a tunneling mechanism. However, it is found that a percolation description not only fits prior data better but provides a much simpler physical mechanism for the more flexible and soft polymer composite prepared and tested in this study. A…