Bacteriostatic Characteristics of Bone Substituting Constructors Obtained from Composite Materials Based on Natural Polymers, Calcium Phosphates and Vancomycin

Abstract

Introduction.The local delivery of therapeutic antibiotic concentrations to the zone of surgical intervention in bone pathology enables either to prevent or significantly decrease the rate of osteomyelitis development. It that study the efficacy of vancomycin inclusion and release from three dimensional constructors based on sodium alginate, gelatin and octacalcium phosphate and vancomycin intended for bone defect substitution was studied.Materials and methods. Prototyping of 3D constructors was performed by extrusion 3D printing. Various concentrations of vancomycin were added as an additional component at the stage of preparation of hydrogel (“ink”) for printing. Physical testing of the constructors included electron microscopic evaluation of their microstructure and porosity as well as the study of mechanical strength for compression and stretching. Functional activity of printed constructors with respect to the test strain S. aureus ATCC 6538-P was assessed by a disc-diffusion method in vitro and on the model of infected excision skin wound in rats -in vivo.Results. Analysis of the kinetic curves showed that the principal release of the drug in the model liquid took place within the first day. The total volume of the bound and released vancomycin made up approximately 20% of the calculated initial amount for all three concentrations. Formation of the marked growth inhibition zone of S. aureus strain in presence of vancomycin rich constructors was demonstrated in vitro. Insertion of constructors into the zone of infected skin defect resulted in a decrease of inflammatory processes severity and rate as well as accelerated the terms of complete wound healing.Conclusion. Study results showed the principle potentiality of bone substituting implants 3D-printing using multicomponent hydrogel compositions without change of separate components characteristics.