Antibiotic loaded ?-tricalcium phosphate/calcium sulfate for antimicrobial potency, prevention and killing efficacy of Pseudomonas aeruginosa and Staphylococcus aureus biofilms

Abstract This study investigated the efficacy of a biphasic synthetic ?-tricalcium phosphate/calcium sulfate (?-TCP/CS) bone graft substitute for compatibility with vancomycin (V) in combination tobramycin (T) or gentamicin (G) evidenced by duration potency and prevention killing efficacies P. aeruginosa (PAO1) S. aureus (SAP231) biofilms vitro assays. Antibiotic loaded ?-TCP/CS beads were compared antibiotic formed from well characterized calcium (CS) void filler. showed antimicrobial against PAO1 repeated Kirby-Bauer like zone inhibition assay 6 days to 8 CS. However, both bead types SAP231 40 days. Both formulations V + T completely prevented biofilm formation (CFU below detection limits) 3 experiment daily fresh inoculum challenges ( P < 0.001). In addition, materials combinations significantly reduced bioburden pre-grown between 5 logs 0.001) G performing slightly better than T. Our data, combined previous data on osteogenesis suggest that may have potential stimulate through acting as scaffold simultaneously protecting infection. Future vivo experiments clinical investigations are warranted more comprehensively evaluate use management orthopaedic infections.