279716 Modulating Electric Fields At Patterned Collectors for the Alignment of Sub-100nm Electrospun Nanofibers
Aligned nanofiber scaffolds are commonly applied within a variety of applications that require highly directional cues, such as tissue engineering, chemical sensing and ferroelectrics. In many cases, scaffolds composed of nanofibers with successively smaller sizes are required. Nanofiber alignment is usually enabled by rotating mandrel-based mechanical approaches  or by electrical approaches for alignment based on field modification using insulator gaps  or dielectrics patterned on the collector . However, the alignment of successively smaller-sized electrospun nanofibers to a high degree is challenging, since smaller fibers experience larger distortions arising from their greater flux and their longer time within the instability region. Furthermore, they are more easily disrupted under shear forces due to alignment using mandrel-based mechanical approaches. Herein, we explore the optimization of electrical methods to enhance the effectiveness of alignment of sub-100 nm fibers through methodologies to vary the transverse field along the nanofiber axis and repulsive fields between neighboring nanofibers due to their residual charge . In this manner, we present a quantitative design methodology for optimizing collector properties, such as gap width, material and permittivity to optimize the spatial extent of the transverse fields, as well as charge density and dielectric properties of the electrospun material to optimize repulsive fields due to residual charge. The application of nanofiber scaffolds aligned through these methods presents a tremendous potential for nerve tissue regeneration .
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