Incorporation of drugs in an amorphous state into electrospun nanofibers composed of a water-insoluble, nonbiodegradable polymer

Abstract

Electrostatic spinning was applied to the preparation of drug-laden nonbiodegradable nanofiber for potential use in topical drug administration and wound healing. The specific aim of these studies was to assess whether these systems might be of interest as delivery systems for poorly water-soluble drugs. Itraconazole and ketanserin were selected as model compounds while a segmented polyurethane (PU) was selected as the nonbiodegradable polymer. For both itraconazole and ketanserin, an amorphous nanodispersion with PU was obtained when the drug/polymer solutions were electrospun from dimethylformide (DMF) and dimethylacetamide (DMAc), respectively. The collected nonwoven fabrics were shown to release the drugs at various rates and profiles based on the nanofiber morphology and drug content. Data were generated using a specially designed release apparatus based around a rotating cylinder. At low drug loading, itraconazole was released from the nanofibers as a linear function of the square root of time suggesting Fickian kinetics. No initial drug burst was observed. A biphasic release pattern was observed for ketanserin in which two sequential linear components were noted. These release phases may be temporally correlated with (1) drug diffusion through the polymer and (2) drug diffusion through formed aqueous pores.