N. S. Sergeeva

Investigation of physicochemical and biological properties of composite matrices in a alginate–calcium phosphate system intended for use in prototyping technologies during replacement of bone defects

Materials for 3D printing of porous composite materials (CM) that are based on sodium alginate–tricalcium phosphate are developed. Physicochemical and biological studies of CM in vitro are performed using a model of two adherent cells lines, immortalized human fibroblasts (HF, strain 1608h TERT) and human osteosarcoma (MG-63) that are cultivated up to 21 days. The cytocompatibility and matrix properties are studied by an MTT assay.

Hybrid composite materials based on chitosan and gelatin and reinforced with hydroxyapatite for tissue engineering

The fundamentals of the technology are developed for the fabrication of hybrid composite chitosan/gelatin-hydroxyapatite materials aimed for medical applications as porous matrices in regenerating damaged bone tissues, and the properties of the above materials are investigated. They are elastic, having a porosity of up to 90% and pores of up to 700 μm in size; possess controlled dissolution kinetics; contain up to 90 wt % hydroxyapatite or carbonate-substituted hydroxyapatite in the form of nanodisperse powders or granules with a size of up to 500 μm; and are characterized by no cytotoxicity. Their introduction into the site of a bone defect considerably accelerates the process of regeneration in a bone tissue.

3D printed constructs with antibacterial or antitumor activity for surgical treatment of bone defects in cancer patients

The concept of functionalization with bioactive molecules and drugs is one of the most advanced areas of modern bone tissue biomaterial science in terms of enhancement of their osteoconductive and therapeutic properties. The purpose of this study was to develop the approaches for 3D printing of sodium alginate /gelatin /octacalcium phosphate-based constructs with antibacterial and antitumor activity intended for bone defects replacement in the patients with malignant diseases. In this work, we evaluated the drug release kinetic and physicochemical characteristics of the constructs, as well as their specific activity, biocompatibility and osteoplastic properties in in vitro and in vivo tests. The experimental results proved the principal possibility of creating the biocompatible bone substitutes with antibacterial/antitumor activity and maintaining osteoconductive properties by means of 3D printing method.

In Vitro Evaluation of the Composite Alginate - Calcium Phosphate Materials for Prototyping Technologies in Bone Defects Substitution

Porous granular composite biomaterials based on sodium alginate and calcium phosphate component: 1% sodium alginate; sodium alginate with gelatin (80/20); calcium phosphate ceramics (CHA, TCP and OCP) and composite materials alginate/CHA, alginate/TCP, alginate/OCP, alginate/gelatin (80/20)/TCP and alginate/TCP/CHA/OCP were investigated for cytotoxicity and matrix (for cells) properties in dynamics of cultivation (up to 21 days). Two adhesive cell lines - immortalized human fibroblasts (HF, strain 1608 hTERT) and human osteosarcoma (MG-63) were used for in vitro MTT assay. OCP material showed its cytotoxicity while all its composites possessed weak matrix properties. For further research on the development of prototyping technologies 3 samples of composite materials were selected: alginate/CHA, alginate/TCP and alginate/gelatin (80/20)/TCP that are characterized by cytocompatibity and the presence of either expressed or moderate matrix properties of the surface for cells.