PREPARATION AND CHARACTERIZATIONS OF ANTIBIOTIC IMPREGNATED MICROPOROUS NANO-HYDROXYAPATITE FOR OSTEOMYELITIS TREATMENT

Abstract

In this study, preparation and characterization of antibiotic-impregnated microporous nano-hydroxyapatite (HA) aiming to function as both antibiotic carrier and bone graft for osteomyelitis treatment were carried out. Microporous nano-hydroxyapatite was prepared by low temperature phosphorization of three-dimensional printed calcium sulfate sample and was impregnated by three types of antibiotics including vancomycin, fosfomycin and gentamicin. Materials properties and antibacterial performance including phase composition, microstructure, degradability, total drug loading, antibacterial activity and shelf life were investigated and reported. Microporous nano-hydroxyapatite having porosity and mean pore size of 63.92% and 0.15 microns was prepared and showed greater resorbability than typical high-temperature sintering samples. Sustained release of antibiotic from the impregnated samples for longer than 29 days was observed, but the difference in the efficiency was related to the difference in the molecular weight, mechanism of action, spectrum of activity of each antibiotic. No deterioration in the antibacterial activity of the prepared antibiotic-impregnated hydroxyapatite was observed after storing for up to 12 months. No cytotoxic potential by MTT assay at all extraction periods was observed for vancomycin-impregnated hydroxyapatite. Gentamicin and fosfomycin impregnated hydroxyapatites showed cytotoxic potential only on day 1 extraction, but no cytotoxic potential was observed on day 2 extraction onward. This could be related to the concentration and characteristics of each released antibiotics.