Electrospun nanofiber meshes: applications in oil absorption, cell patterning, and biosensing

Abstract

Nanofabrication techniques produce materials with enhanced physicochemical properties through a combination of nanoscale roughness and the use of chemically diverse polymers which enable advanced applications in separation science (air/water purification), tissue engineering, and biosensing. Since the late 1990’s, electrospinning has been extensively studied and utilized to produce nano- to microfiber meshes with 3D porosity on the gram scale. By combining a high surface area to volume ratio and tunable surface chemistry, electrospinning is a facile platform for generating non-woven polymeric fibers for many biomedical and industrial applications. This thesis describes three applications of electrospun nano- and microfiber meshes spun from both commercially available and novel polymer systems for: 1) oil and water separation after an accidental oil spill; 2) ultraviolet light controlled protein and cell patterning throughout 3-dimensional nanofiber meshes; and 3) novel diagnostic platform by combining electrospun nanofiber meshes with solid state nanopores for enhanced single molecule nucleic acid and protein detection.

Each application embodies the philosophy that electrospun materials have the potential to solve a wide variety of problems by simply tuning the physicochemical properties and mesh morphologies towards the design requirements for a specific problem. For example, to solve the problem of recovering crude oil after an oil spill while generating a minimal waste burden, a hydrophobic and biodegradable microfiber mesh was designed to repeatedly separate oil and water and naturally biodegrade after use. In order to solve the problem of spatiotemporal placement of cells within a 3-dimensional tissue engineering construct, an ultraviolet light activated mesh was designed to transition from hydrophobic (water impermeable) to hydrophilic (water permeable) upon exposure to ultraviolet light facilitating protein and cell patterning. Finally to address two problems with single molecule solid state nanopore biosensors, namely rapid nucleic acid translocation rates and limited protein identification capabilities, a new biosensor platform was developed based on two novel polymeric systems which were synthesized and electrospun into high surface area nanofiber mesh coatings.