Drug release, cytocompatibility, bioactivity, and antibacterial activity of doxycycline loaded Mg-Ca-TiO2 composite scaffold

Mg-Ca-TiO2 (MCT) composite scaffolds loadedwith different concentrations of doxycycline (DC) with a network of interconnected pores with good compressive strength (5 +/- 0.1 MPa) were fabricated via space holder method for the first time. The results showed that MCT-DC scaffolds possess a porosity and pore size in the range of 65-67% and 600-800 mu m respectively. The bioactivity results exhibited the apatite formation on the MCT-DC scaffold surface, indicating that DC did not obstruct the bioactivity of MCT. The MCT-DC scaffolds drug release profiles show the initial burst and sustained drug release (55-75%) and the release rate could be adjusted via altering the DC concentration. The MCT loadedwith 1 and 5% DC did not indicate cytotoxic behavior against MG63 cells while further DC loading resulted in some toxicity. Antimicrobial properties of MCT-DC scaffolds against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria were examined and the results reveal oblivious inhibition zone around each MCT-DC scaffold whereas no obvious inhibition is observed around the MCT scaffold. Therefore, MCT-DC composite scaffolds with low concentration of DC could be alternative candidates for infection prevention and bone tissue engineering. (C) 2017 Published by Elsevier Ltd.