Enhancement of antibacterial properties of α-tricalcium phosphate/honey biocement using glucose oxidase

The antibacterial properties of a simple cement composite based on powdered α-tricalcium phosphate phase and liquid component containing honey and glucose oxidase were studied on Escherichia coli and Staphylococcus aureus. The content of active glucose substrate and glucose oxidase in the composites was around 2 wt% and up to 10 ppm, respectively. The applied amounts were sufficient to produce hydrogen peroxide at effective concentration levels (up to 800 μM) against the studied bacterial strains with low cytotoxicity to osteoblastic cells. The results showed strong adsorption of glucose oxidase on the surface of the transformed α-tricalcium phosphate phase with a decrease in enzyme activity in phosphate-buffered saline, but after supplementation with serum, the enzyme activity increased approximately fourfold due to partial enzyme desorption from the surface of the cement particles. The method used may represent a very effective way to increase the antibacterial properties of bone cements, especially in bacterial wound infection, treatment of contaminated fractures or postoperative infections.