Biodegradable implants of gentamicin sulfate for effective management of osteomyelitis

The purpose of the present study was to prepare and evaluate rod shaped biodegradable implants of gentamicin sulfate using poly(ε-caprolactone) (PCL). The implants were prepared by melt extrusion method with different ratios of drug and PCL (1:1, 1:1.5 and 1:2) and evaluated for drug content, in vitro drug release, stability studies and in vivo evaluation in healthy rabbits. The implants were found to be uniform with respect to weight, diameter, length and drug content. In the in vitro drug release studies, implants released the drug in a biphasic pattern with an initial burst release followed by a slow release over a period of 80 days. In the in vivo experiment, the gentamicin concentration of bone was maintained above the minimum inhibitory concentration for Staphylococcus aureus over a period of 4 weeks. In the stability studies, the implants exhibited no change in the drug content after 6 months at refrigeration temperature and 25 °C. The present study reveals the applicability of biodegradable gentamicin implants to treat bone disorders.