Novel Porous Barium Titanate/Nano-bioactive Glass Composite with High Piezoelectric Coefficient for Bone Regeneration Applications

摘要

Recently, porous bioceramics are widely used in bone tissue engineering in order to the regeneration of damaged tissues. Piezoelectric effect in bone plays a very important role in bone regeneration. Therefore, the purpose of this study was the fabrication of porous barium titanate (BT)/nanobioglass (nBG) scaffold (vol.% BT = 75% and 90%) with high piezoelectric coefficient by freeze casting technique. For this purpose, BT and nBG powders were synthesized using solid-state and sol-gel methods, respectively. Partial recrystallization of nBG phase during sintering process occurred. The highly oriented lamellar microstructure of the fabricated BT90/nBG10 scaffold with open/interconnected porosities observed. The BT75/nBG25 composite scaffold exhibited higher value of density (1.18 +/- 0.1 g/cm(3)) and lower amount of porosities (77 +/- 1%) compared to the BT90/nBG10 scaffold (0.99 +/- 0.1 g/cm(3)and 82 +/- 1%). The piezoelectric coefficients of the BT90/nBG10 and BT75/nBG25 composite scaffolds obtained 36 pC/N and 24 pC/N which were much higher than that of the natural human bone. The BT75/nBG25 scaffold showed more compressive strength (16.9 +/- 1.1 MPa) than that of BT90/nBG10 composite scaffold (8.1 +/- 0.3 MPa). The MTT results after 24, 72 and 168 h of culture showed that both composites had acceptable cell viability and cells were able to adhere, proliferate and migrate into pores of the scaffolds. Furthermore, cell density and adhesion were little bit higher in the BT75/nBG25 composite. These results indicated that highly porous barium titanate scaffolds have great potential in tissue engineering applications for bone tissue repair and regeneration.