In this work, a novel drug delivery system consisting of poly(ε-caprolactone) (PCL) electrospun fibers containing an ad-hoc-synthesized star polymer made up of a poly(amido-amine) (PAMAM) core and PCL branches (PAMAM-PCL) was developed. The latter system which was synthesized via the ring opening polymerization of ε-caprolactone, starting from a hydroxyl-terminated PAMAM dendrimer and characterized by means of H NMR, IR and DSC, was found to be compatible with both the polymer matrix and a hydrophilic chemotherapeutic drug, doxorubicin (DOXO), the model drug used in this work. The preparation of the dendritic PCL star product with an average arm length of 2000g/mol was characterized using IR andH NMR measurements. The prepared star polymer possessed a higher crystallinity and a lower melting temperature than that of the used linear PCL. Electrospun fibers were prepared starting from solutions containing the neat PCL as well as the PCL/PAMAM-PCL mixture. Electrospinning conditions were optimized in order to obtain defect free fibers, which was proven by the structural FE-SEM study. PAMAM moieties enhanced the hydrophilicity of the fibers, as proved by comparing the water absorption for the PCL/PAMAM-PCL fibers to that neat PCL fibers. The drug-loaded system PCL/PAMAM-PCL was prepared by directly introducing DOXO into the electrospinning solutions. The DOXO-loaded PCL/PAMAM-PCL showed a prolonged release of the drug with respect to the DOXO-loaded PCL fibers and elicited effective controlled toxicity over A431 epidermoid carcinoma, HeLa cervical cancer cells and drug resistant MCF-7 breast cancer cells. On the contrary, the drug-free PCL/PAMAM-PCL scaffold demonstrated no toxic effects on human dermal fibroblasts, suggesting the biocompatibility of the proposed system which can be used in cellular scaffold applications.

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Polymer piezoelectric nanogenerators have attracted attention for mechanical energy harvesting, for powering wearable electronics and movement sensing applications. Polyvinylidene fluoride (PVDF) is a flexible and efficient electroactive polymer, however, it is a polymorph for which only two phases (of five) are piezoelectric. Herein are produced breathable and flexible textile‐compatible electroactive mats via electrospinning, and the polymorphism of PVDF nanofibers during deposition is controlled, rather than post‐fabrication, meaning that this process is directly compatible with textile manufacturing. The electrospinning process combines mechanical stretching and electrical poling and results in the alignment of dipoles in the nanofibers. The local stretching of polymer chains at each position on the fibre point impacts the polymorph relative content in that area. It is found that finer PVDF fibres (ø < 50 nm) have a lower electroactive crystal phase content compared to medium thickness‐range fibres (100 nm < ø < 500 nm), whilst thicker fibres (ø > 1000 nm) show distinct areas of lower (fibres with beading) and higher (smooth fibres) electroactive phase content. Ultimately, fibrous mats produced using solutions with a high polymer concentration have a lower bead content and the most uniform medium‐range fibre thickness, consequently resulting in the highest content of the electroactive phase.