Novel poly-DL-lactide-polycaprolactone copolymer based flexible drug delivery system for sustained release of ciprofloxacin

This research evaluated 7525DLPCL for soft flexible drug delivery systems. The effect of ciprofloxacin hydrochloride (CIP) loading at three levels (10, 20, and 30%), on thermo-mechanical properties was studied. CIP release was monitored for 12 weeks. Addition of CIP to 7525DLPCL caused an increase in compressive modulus of 7525DLPCL. CIP release was found to be sigmoidal with two phenomena (apart from a minor burst) contributing to release-diffusion and later diffusion plus erosion. An increased burst was observed with greater CIP loading and the majority of CIP (> 70%) was released as an effect of diffusion plus erosion. Additional factors, like the effect of CIP particle size, had no significant effect on drug release. Change in the implant shape from a cylinder (5 mm diameter; 3 mm thickness) to disc (6 mm diameter, 0.5 mm thickness) also failed to show a significant impact on drug release. Erosion of 7525DLPCL is a major contributing factor towards this release and other factors like shape of implants and particle size of drug have little effect on CIP release. Such flexible drug delivery systems offer new avenues for long-term skeletal drug delivery of antibiotics for conditions like osteomyelitis or periodontitis.