Dennis Edmondson

The ability to produce well-blended nanofibers from natural and synthetic polymers represents a significant advancement in development of composite materials with desired structures and material properties. The nanofiber presented here exhibits excellent structural stability and mechanical and biological properties favorable for biomedical applications, and offers a new nanofibrous platform for development of matrices for various biomedical applications. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Well-ordered one-dimensional nanostructures are enabling important new applications in textiles, energy, environment and bioengineering owing to their unique and anisotropic properties. However, the production of highly aligned nanofibers in a large area remains a significant challenge. Here we report a powerful, yet economical approach that integrates the concepts of the parallel-electrode electrospinning with centrifugal dispersion to produce nanofibers with a high degree of alignment and uniformity at a large scale. We first demonstrated this approach with polyvinylidene fluoride to show how experimental parameters regulate fiber properties, and then with chitosan, a natural polymer, and polyethylene oxide, a synthetic polymer, to illustrate the versatility of the system. As a model application, we then demonstrated the significance of fiber alignment in improving the piezoelectric effect for voltage generation. The technique presented here may be used for mass production of aligned nanofibers of various polymers for a myriad of applications.

In vitro models that accurately mimic the microenvironment of invading glioblastoma multiform (GBM) cells will provide a high-throughput system for testing potential anti-invasion therapies. Here, the ability of chitosan-polycaprolactone polyblend nanofibers to promote a migratory phenotype in human GBM cells by altering the nanotopography of the nanofiber membranes is investigated. Fibers are prepared with diameters of 200 nm, 400 nm, and 1.1 μm, and are either randomly oriented or aligned to produce six distinct nanotopographies. Human U-87 MG GBM cells, a model cell line commonly used for invasion assays, are cultured on the various nanofibrous substrates. Cells show elongation and alignment along the orientation of aligned fibers as early as 24 h and up to 120 h of culture. After 24 h of culture, human GBM cells cultured on aligned 200 nm and 400 nm fibers show marked upregulation of invasion-related genes including β-catenin, Snail, STAT3, TGF-β, and Twist, suggesting a mesenchymal change in these migrating cells. Additionally, cells cultured on 400 nm aligned fibers show similar migration profiles as those reported in vivo, and thus these nanofibers should provide a unique high-throughput in vitro culture substrate for developing anti-migration therapies for the treatment of GBM.