Calcium phosphate and composite materials functionalization of bioactive agents for its target delivery to the bone

Aim of the study. The development of the method of octacalcium phosphate (OCP) and mineral-polymer composite material functionalization with biological agents (human platelet lysate (PL) growth factors and antibiotic vancomycin) by the biomimetic coprecipitation principle technique. Materials and methods. The OCP and the mineral-polymer composite matrices (sodium alginate / gelatin / OCP) functionalization was obtained by biomimetic coprecipitation of calcium phosphates and the bioactive molecules on their surface. The materials structure was examined by electron microscopy. The functionalization efficiency was determined by measurement of the incorporated compounds in solution, as well as by analysis of their release over the 8 days. The antimicrobial activity of vancomycin functionalized samples was evaluated by in vitro disk diffusion method against the Staphylococcus aureus strain. Results. The evaluation of incorporated molecules release showed that the OCP functionalization with vancomycin is more effective than PL. The antibiotic release had continued for three days, while PL growth factors — only for 30 minutes. The incorporated into a composite matrix vancomycin was completely released within 24 h. In vitro study of the functionalized composite samples showed growth delay of the Staphylococcus aureus strain in dependence on antibiotic content. Conclusion. The developed method of drug incorporation during biomimetic precipitation allowed to create target delivery system which transfer antibiotic to the bone defect.