These thicker nanofiber microstructures, especially beneficial for tissue scaffolding, are developed using an immersion lithography technique that overcomes limitations inherent in other nanofiber lithography. Nanofibers are extremely small fibers that can be constructed into specific patterns using a process called lithography. (Consider that a single human hair is about 50,000-100,000 nanometers thick.) In lithography, an ultraviolet light solidifies a prepared nanofiber pattern into a structure; some structures are used as a scaffold for tissue. The tissue scaffolding industry was valued at $3.5 billion in 2012. Flexible nanofiber structures are ideal for tissue scaffolding, as they are completely biocompatible and can be formed into many patterns via lithography. UV lithography in the medium of air has limited resolution due to diffraction of light; the alternative, the hydrogel embedded nanofiber tissue scaffold, is porous only on the bottom layer. Researchers at the University of Florida have developed an oil immersion lithography that decreases diffraction, increases resolution, and creates tissue scaffolds that are porous on all sides -- all in one step that reduces costs and minimizes human error. The superior result is a larger, thicker, and more stable 3D nanofiber microstructure.
Lithography that uses oil, improving quality and stability of 3D nanofiber microstructures
In this immersion lithography developed by UF researchers, nanofibers are immersed in an oil medium and are directly photopatterned in the oil medium using UV light. This creates a better substrate than air for many industries and uses, especially tissue scaffolding, and reduces the process to one step, improving accuracy. This photopatternable nanofiber can be used to mimic bio-inspired architectures. This electrospun nanofiber is compatible with a variety of substances.