Stimuli-responsive nanofibers prepared from poly(N-isopropylacrylamide-acrylamide-vinylpyrrolidone) by electrospinning as an anticancer drug delivery

In this study, stimuli-responsive nanofibers (NFs) were successfully prepared via electrospinning method. Poly(N-isopropylacrylamide-co-acrylamide-co-vinylpyrrolidone) P(NIPAAM-AAm-VP) was used as the material for preparing the electrospinning NFs. Doxorubicin (Dox)-loaded NFs were prepared and characterized by XRD, Scanning electron microscopy and FTIR. A response surface methodology was used to evaluate the effect of key parameters on the fiber diameter. The cytotoxicity of Dox-loaded NFs was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole assay on lung cancer A549 cell lines. In vitro cytotoxicity assay showed that the P(NIPAAM-AAm-VP) fibers themselves did not affect the growth of A549 cells. Antitumor activity of the Dox-loaded fibers against the cells was kept over the whole experimental process, while that of pristine Dox disappeared within 48h. Drug release pattern from these systems is in zero order and drug release rate is not dependent on drug/polymer ratio in different implant formulations. These novel NFs were stable and preserved their morphology even after incubation in release medium (pH 7.4, 37 degrees C), while collapsed and dispersed quickly in aqueous solution of acidic medium at room. The reported incorporation of stimuli-responsive properties into NFs takes advantage of their extremely large surface area and porosity and is expected to provide a simple platform for smart drug delivery.