Tunable release of Chlorhexidine from Polycaprolactone-based filaments containing graphene nanoplatelets

Abstract

Graphene nanoplatelets (GNP) as fillers and Chlorhexidine (CHX), as an antibacterial agent, were incorporated in a polycaprolactone (PCL) matrix and processed into filaments by melt spinning. The influence of both drawing and formulation on the processability, spinnability, mechanical properties and release behaviour of these materials were deeply investigated by performing rheological, morphological analysis, tensile tests, and by measuring the cumulative release of CHX in PBS at 37 °C. Furthermore, Korsmeyer–Peppas model was adopted to study the kinetics release mechanism. The results showed that adding GNP did not alter the processability and spinnability of the systems. Furthermore, a monotonic trend of all of the properties investigated was found as a function of GNP/CHX ratio and DR: stiffness and tensile strength of such fibers were found to increase, and the release behaviour proved to be tunable. In fact, upon increasing GNP content, burst was progressively hindered at the initial stage of release, while being progressively enhanced the kinetics and amount of CHX at the final stage.