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Two drawbacks of the traditional electrospinning process when used for producing nanofibers for drug release are that clogging of the spinneret is often experienced, and the fibers produced often exhibit a tailing-off of drug release over sustained periods. The present study investigates the preparation of ferulic acid (FA) sustained-release cellulose acetate (CA) nanofibers, in which a third component, polyvinylpyrrolidone (PVP), was included into the nanocomposites for an improved sustained drug release profile. A modified coaxial electrospinning process, in which only organic solvent N, N-dimethylacetamide was used as a sheath fluid, was exploited for a smooth and continuous fabrication of multiple-component nanofibers. Under an applied voltage of 16 kV and an optimized sheath-to-core flow rate ratio of 0.11, three types of FA/PVP/CA composite nanofibers (with varied of PVP content) were generated. These nanofibers had higher quality in terms of size and distribution of nanofiber diameter, as indicated by FESEM images. Analysis of double- and triple-component nanofibers by XRD, DSC, and ATR-FTIR confirmed the compatibility of components producing homogenous fibers in both cases, but the triple-component nanofibers exhibited better release profiles over sustained periods than the double-component nanofibers in terms of release completeness, reduced tailing-off, and adjustable release rates. The modified coaxial process and the resulting multiple-component nanocomposites should provide a new way for developing novel drug sustained materials and drug delivery systems. [ABSTRACT FROM AUTHOR]

Composite materials based on poly(ε-caprolactone) (PCL) and carbon nanofibres (CNFs) were processed by solvent casting and electrospinning. The main objective was to investigate the effects of the CNFs on the microstructural, thermal and mechanical properties of the PCL matrix composites processed by two different routes. The hybrid materials obtained with different CNF content (1, 3 and 7 wt%) were analysed by electron microscopy (FESEM), differential scanning calorimeter (DSC), thermogravimetry (TGA) and mechanical testing. The composite films showed a good dispersion in the PCL matrix while electrospun samples were consisted of homogeneous and uniform fibres up to 3 wt% CNFs with average fibre diameter ranged between 0.5 and 1 μm. Composite films and mats revealed an increased crystallization temperature with respect to the neat PCL matrix. Mechanical properties of solvent cast films and electrospun mats were assessed by uniaxial tensile tests. A stiffness increase was achieved in PCL films depending on the CNF content, while mechanical properties of mats were only slightly affected by CNF introduction. [ABSTRACT FROM AUTHOR]