RESUMO
In this study, three natural biomaterials, Locust bean gum (LBG), Xanthan gum (XG), and Mastic gum (MG), were combined to form cryogel scaffolds. Thermal and chemical characterizations revealed the successful blend formation from LBG-XG (LX) and LBG-XG-MG (LXM) polymers. All blends resulted in macro-porous scaffolds with interconnected pore structures under the size of 400⯵m. The swollen cryogels had similar mechanical properties compared with other polysaccharide-based cryogels. The mean tensile and compressive modulus values of the wet cryogels were in the range of 3.5-11.6â¯kPa and 82-398â¯kPa, respectively. The sustained release of the small molecule Kartogenin from varying concentrations and ratios of cryogels was in between 32 and 66% through 21â¯days of incubation. Physical, mechanical, and chemical properties make LX and LXM polysaccharide-based cryogels promising candidates for cartilage and other soft tissue engineering, and drug delivery applications.
Assuntos
Criogéis/química , Preparações de Ação Retardada/química , Alicerces Teciduais/química , Anilidas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Criogéis/toxicidade , Preparações de Ação Retardada/toxicidade , Liberação Controlada de Fármacos , Galactanos/química , Galactanos/toxicidade , Mananas/química , Mananas/toxicidade , Resina Mástique/química , Resina Mástique/toxicidade , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Células NIH 3T3 , Ácidos Ftálicos/química , Gomas Vegetais/química , Gomas Vegetais/toxicidade , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/toxicidade , Porosidade , Ratos Sprague-Dawley , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodosRESUMO
A large variety of approaches have been used to treat large and irregular shaped bone defects with less than optimal success due to material or design issues. In recent years patient specific constructs prepared by additive manufacturing provided a solution to the need for shaping implants to fit irregular defects in the surgery theater. In this study, cylindrical disks of poly(ε-caprolactone) (PCL) were printed by fused deposition modeling and modified with nanohydroxyapatite (HAp) and poly(propylene fumarate) (PPF) to create a mechanically strong implant with well-defined pore size and porosity, controllable surface hydrophilicity (with PPF) and osteoconductivity (with HAp). Cytotoxicity, irritation and inflammation tests demonstrated that the scaffolds were biocompatible. PCL/HAp and PCL/HAp/PPF scaffolds were implanted in the femurs of rabbits with and without seeding with rabbit Bone Marrow Stem Cells (BMSC) and examined after 4 and 8 weeks with micro-CT, mechanically and histologically. BMSC seeded PCL/HAp/PPF scaffolds showed improved tissue regeneration as determined by bone mineral density and micro-CT. Compressive and tension stiffness values (394 and 463 N mm-1) were significantly higher than those of the healthy rabbit femur (316 and 392 N mm-1, respectively) after 8 weeks of implantation. These 3D implants have great potential for patient-specific bone defect treatments.