Release of antibiotics from electrospun bicomponent fibers

Biocompatible nanofibers that are capable of adapting to the physiological conditions of the human body have become increasingly important for clinical applications in recent years. Electrospun fiber mats offer particular advantages due to their large surface area and their sorption/release properties. If loaded with drugs, delivery properties can be tailored to a specific release rate. This research work focuses on poly(L-lactic acid) (PLA) and poly(epsilon-caprolactone) (PCL) incorporating three different model antibiotics as well as bicomponent fibers made from PLA and PCL containing the same model drugs. Tetracycline and chlorotetracycline hydrochloride, and amphotericin B were selected as model drugs and their release properties and antimicrobial effectiveness studied. The surface morphology and the average diameter of the fibers strongly depended on the individual spinning system which in turn influenced the release of the therapeutic compounds from the fibers. Tetracycline was discharged from PCL at the highest rate while amphotericin B was slowest. PCL almost completely liberated any of the drugs over time while PLA only released about 10% total. By forming bicomponent PCL-PLA fibers surface and release characteristics could be modified to fit a sensible drug delivery.