Polycaprolactone nanofibers loaded oxytetracycline hydrochloride and zinc oxide for treatment of periodontal disease.

Periodontal diseases (PD) are mixed bacterial infections caused by microorganisms that colonize the tooth surface, leading to destructions at tooth-supporting tissues. Several local delivery systems, as nanofibers, have been developed for the treatment of PD. The purpose of the present study was developing polycaprolactone (PCL) nanofibers incorporating two antibacterial agents, OTC and ZnO, for use in the treatment of PD. Nanofibers were produced by electrospinning method: PCL loaded with ZnO (PCL-Z), PCL loaded with OTC (PCL-OTC), PCL loaded with OTC and ZnO (PCL-OTCz) and pristine PCL (PCL-P). The nanofibers were characterized physicochemically using different techniques. In addition, in vitro study of the OTC release from the nanofibers was performed. The PCL-OCT showed sustained release of the drug up to 10 h, releasing 100% of OTC. However, the PCL-OTCz nanofiber showed a slow release of OTC up to 120 h (5th day) with 54% of drug retention. The cytotoxicity assay showed that PCL-OTC nanofiber was slightly cytotoxic after 48 h and the other nanofibers were non-cytotoxic. The antibacterial activity of the nanofibers was evaluated by qualitative and quantitative analysis and against mixed bacterial culture, composed of four Gram-negative anaerobic bacteria involved in periodontal diseases. The disk diffusion method showed that the PCL-OTC displayed higher inhibition zone than PCL-OTCz (p < 0.001). The quantitative analysis, evaluated by broth culture, showed that the PCL-OTC and PCL-OTCz exhibited excellent activity against a mixed bacterial culture with growth inhibition of 98.0% and 97.5%, respectively. Based on these results, the PCL-OTCz nanofibers developed have great potential as a drug delivery system for the PD treatment.