To conclude, the formation of heterogeneously shaped microfilaments (48 ± 12 µm, mean ± S.D.) was achieved in a standard FDM 3D Printer with the strategies developed in this work, and it was found that the optimum conditions for obtaining such microfibers were high speeds and a reduced extrusion multiplier. To evaluate the influence of these printing conditions on the creation of internal patterns at the microscopic level, an optical analysis of the printed scaffolds was carried out using a digital microscope and subsequent image analysis with ImageJ software. For this purpose, novel algorithms generating deposition routines (G-code) based on primitive geometrical figures were created by python scripts, modifying basic deposition conditions such as temperature, speed, or material flow. This work studies the possibility of creating reproducible microscopic internal fibers inside scaffolds printed by standard 3D printing. New additive manufacturing techniques, such as melting electro-writing (MEW) or near-field electrospinning (NFES), are now used to include microfibers inside 3D printed scaffolds as FDM printers present a limited resolution in the XY axis, not making it easy to go under 100 µm without dealing with nozzle troubles. The obtained results suggest that the CS/HAp scaffolds have great potential as biocompatible materials for BTE applications. The presence of HAp mimicking biological apatite in the composite scaffolds facilitated a higher protein adsorption capability, compared to that of the CS scaffolds. The CS/HAp scaffolds demonstrated a higher biomineralization capability than that of the CS scaffolds, releasing a bone-like apatite layer on their surface after 15 days of incubation in simulated body fluids. The addition of HAp into the CS matrix efficiently decreased the swelling percentage of the CS/HAp scaffolds and retained the suitable degradation rate of the composite scaffolds the degradation percentage of the CS/HAp scaffolds was 46.37% after 28 days immersed in a physiological solution. Results showed that the 3D CS/HAp scaffolds exhibited highly porous structures with an average pore size of 265 μm, and mean porosity of 75.01%, respectively the tensile strength of the scaffolds was 2.45 MPa, matching well with that of cancellous bone. The biodegradation, biomineralization and protein adsorption capabilities of the scaffolds were evaluated through tests in vitro. Fourier transform infrared spectroscopy was also conducted to investigate the interaction between chitosan (CS) and hydroxyapatite (HAp). The scaffolds were prepared by the freeze-drying method, then characterized by X-ray diffraction, scanning electron microscopy, liquid substitution, swelling behavior, and mechanical strength. This work presents the enhanced biomineralization and protein adsorption capacity of 3D chitosan/hydroxyapatite (CS/HAp) biomimetic scaffolds synthesized from natural sources applied for bone-tissue engineering (BTE).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |