Functionalized graphene oxide modified polysebacic anhydride as drug carrier for levofloxacin controlled release

Functionalized graphene oxide modified polysebacic anhydride composites were synthesized by Steglich esterification and characterized by various techniques such as Fourier transform-infrared spectrometry, differential scanning calorimetry, gel permeation chromatography, X-ray powder diffraction, dynamic light scattering, and scanning electron microscopy. In the release study using these composites, the release kinetics of drug loaded composites were studied in phosphate buffer saline, when the pH value was 7.4, at 37 degrees C using levofloxacin as a model antibacterial drug. In contrast to the pure polysebacic anhydride, different feeding ratio of graphene oxide modified polysebacic anhydride provides much longer drug release duration, and the drug release duration could be controlled by the molecular weight of the composites. In addition, the 2% graphene oxide modified polysebacic anhydride (M-w = 5000 D) exhibits a nearly perfect linear release behavior with an extended release time as long as 80 days, and the effective drug release amount exceeding 95%. The results of XRD indicated that the prepared graphene oxide contains adsorbing water, and it led to an obvious decrease in the molecular weight of polysebacic anhydride grafted on graphene oxide. This has affected the release behaviors to a certain extent. High molecular weight polysebacic anhydride grafted on dried graphene oxide and their release behaviors will be provided in our future work.