Sustained release of ketoprofen from fibrous chitosan-poly(ɛ-caprolactone) membranes

Chitosan-poly(ɛ-caprolactone) was fabricated into drug-enclosed fibrous membranes by loading with ketoprofen and using a wet-spinning method. The optimized chitosan-poly(ɛ-caprolactone) fibrous membranes with poly(ɛ-caprolactone) proportions changing from about 20 to 40 wt% showed notably enhanced tensile strength in wet state as compared to pure chitosan fibrous membranes. Some membranes loaded with an initial amount of around 8 wt% ketoprofen were capable of maintaining sustained releases of ketoprofen for a period of time longer than 50 h without significant initial burst release, and the corresponding release profiles could be effectively controlled by regulating the composition and diameters of the filaments. Kinetic analysis indicated that ketoprofen-release patterns from selected membranes were well fitted with Higuchi model and showed biphasic characteristics with different release-rate constants depending on the parameters of the membranes; and ketoprofen-releases were administrated by anomalous mechanisms involved both initial swelling and follow-up diffusion.