Serra, Tiziano, Ortiz Hernández, Mónica, Engel López, Elisabeth, Planell Estany, Josep Anton, Navarro Toro, Melba Eugenia, Universitat Politècnica de Catalunya. Departament de Ciència dels Materials i Enginyeria Metal·lúrgica, Institut de Bioenginyeria de Catalunya, and Universitat Politècnica de Catalunya. BBT - Biomaterials, Biomecànica i Enginyeria de Teixits
Àrees temàtiques de la UPC::Enginyeria dels materials, Tissue engineering, Tissue scaffolds, Rapid prototyping, Scaffold, Polylactic acid, Surface characterization, 3D-printing, POLY(LACTIC ACID), POLY(ETHYLENE GLYCOL), COMPOSITE SCAFFOLDS, PHOSPHATE-GLASSES, IN-VITRO, BONE, CRYSTALLIZATION, DEGRADATION, FABRICATION, DEPOSITION, Enginyeria de teixits, and Teixits -- Bastides
Achieving high quality 3D-printed structures requires establishing the right printing conditions. Finding processing conditions that satisfy both the fabrication process and the final required scaffold properties is crucial. This work stresses the importance of studying the outcome of the plasticizing effect of PEG on PLA-based blends used for the fabrication of 3D-direct-printed scaffolds for tissue engineering applications. For this, PLA/PEG blends with 5, 10 and 20% (w/w) of PEG and PLA/PEG/bioactive CaP glass composites were processed in the form of 3D rapid prototyping scaffolds. Surface analysis and differential scanning calorimetry revealed a rearrangement of polymer chains and a topography, wettability and elastic modulus increase of the studied surfaces as PEG was incorporated. Moreover, addition of 10 and 20% PEG led to non-uniform 3D structures with lower mechanical properties. In vitro degradation studies showed that the inclusion of PEG significantly accelerated the degradation rate of the material. Results indicated that the presence of PEG not only improves PLA processing but also leads to relevant surface, geometrical and structural changes including modulation of the degradation rate of PLA-based 3D printed scaffolds. (C) 2014 Elsevier B.V. All rights reserved.
Serra, Tiziano, Planell Estany, Josep Anton, Navarro Toro, Melba Eugenia, Universitat Politècnica de Catalunya. Departament de Ciència dels Materials i Enginyeria Metal·lúrgica, and Universitat Politècnica de Catalunya. BBT - Biomaterials, Biomecànica i Enginyeria de Teixits
Àrees temàtiques de la UPC::Enginyeria dels materials, Tissue scaffolds, Biodegradable, Composite, Polylactic acid, Rapid prototyping, Scaffold, and Teixits -- Bastides
Fabrication of new biodegradable scaffolds that guide and stimulate tissue regeneration is still a major issue in tissue engineering approaches. Scaffolds that possess adequate biodegradability, pore size, interconnectivity, bioactivity and mechanical properties in accordance with the injured tissue are required. This work aimed to develop and characterize three-dimensional (3-D) scaffolds that fulfill the aforementioned requirements. For this, a nozzle-based rapid prototyping system was used to combine polylactic acid and a bioactive CaP glass to fabricate 3-D biodegradable scaffolds with two patterns (orthogonal and displaced double layer). Scanning electron microscopy and micro-computer tomography showed that 3-D scaffolds had completely interconnected porosity, uniform distribution of the glass particles, and a controlled and repetitive architecture. Surface properties were also assessed, showing that the incorporation of glass particles increased both the roughness and the hydrophilicity of the scaffolds. Mechanical tests indicated that compression strength is dependent on the scaffold geometry and the presence of glass. Preliminary cell response was studied with primary mesenchymal stem cells (MSC) and revealed that CaP glass improved cell adhesion. Overall, the results showed the suitability of the technique/materials combination to develop 3-D porous scaffolds and their initial biocompatibility, both being valuable characteristics for tissue engineering applications.