Some physicochemical and biological characteristics of 3D printed constructions based on sodium alginate and calcium phosphates for bone defects reconstruction

A creation of personalized constructions for tissue engineering of bone tissue is very perspective biomedical technological trend. An aim of our work was studying physicochemical characteristics, cyto- and biocompatibility of 3D printed constructions based on sodium alginate and three calcium phosphates species (tricalcium phosphates, carbonated hydroxyapatite, and octacalcium phosphate). The methods of 3D constructions producing included 3D printing of components with crosslinking agent (CaCl2), their freezing, sublimation, “forced shrinkage”, γ-ray sterilization (15 kGr). A structure of 3D constructions, their porosity and strength characteristics were studied. The cytocompatibility of 3D constructions and matrix-for-cell properties were investigated in vivo on a model of human osteosarcoma MG-63 cell line by means of MTT assay. The biocompatibility of 3D constructions was studied on the model of subcutaneous implantation in mice up to 12 weeks Using scanning electron microscopy it was found that all 3 types of constructions have a lamellar structure of alginate component with spherical inclusions of calcium phosphate Total porosity of species was 54,5-63,9%. Calcium phosphates in the constructions reserved initial phase composition Compressive strength of 3D constructions depended on inorganic component and was 1,8-3,7 MPa with ultimate strain 12,3-12,6%. All types of 3D constructions were cytocompatible in vitro, demonstrated good matrix-forcells properties, and had supported cell proliferation for 2 weeks. in results of subcataneous in vivo test all constructions demonstrated biocompatibility with slow bioresorption of organic and inorganic components. Received data proved the promising outlook for further improvement of 3D printing and investigations of described 3D constructions as osteoplastic materials

3D-printing, sodium alginate, calcium phosphates, biocompatible materials, bone regeneration