2021-08-172021-08-172020-082020-08August 202https://hdl.handle.net/2346/87648Tissue engineering has emerged as an alternative cell-based approach, aiming at replacement of damaged organs with in vitro generated tissue equivalents. Electrospinning has shown great potential in tissue engineering due to its versatile capabilities to create fibrous assemblies with structures mimicking extracellular matrix (ECM). This technique enables engineering scaffolds with multiple unique properties including micro to nanoscale topography, high porosity, and high surface to volume ratio. These properties are critical for enhancing cell attachment, regulating drug release, and promoting mass transfer properties. Fabrication of biomimetic cell microenvironment closely resembling the native tissues has become the latest strategy for regenerative medicine. However, it remains challenging to create scaffolds with tunable biomimetic microstructure close to native fibrous extra-cellular matrix on a clinically relevant scale. This research presented three novel electrospinning strategies to address this challenge. First, a rotation electrospinning system with a cone collector was developed to generate 2D fibrous mat with microtopology gradient. Multivariate analysis of variance (MANOVA) showed that the tip-to-axis distance (TAD) and rotation speed (RS) significantly influenced the gradient features including fiber diameter and fiber alignment. Second, a divergence electrospinning system was developed to create 3D scaffold comprising of aligned nanofibers. Factorial experiment revealed that inclination angle and length-to-width ratio influenced the electric field distribution and fiber gradients. The scaffolds provided topographical cues to promote human fibroblast cell adhesion, proliferation, and morphogenesis in 3D space. Future parametric and mechanism studies on materials properties such as viscosity, conductivity, and ambient parameters such as temperature are needed to establish quantitative relationships between process parameters and attribute gradients. In addition, a statistical model will be developed to predict the fiber distribution and geometry within the divergence electrospun scaffold. Thirdly, a novel electrospinning approach was developed to fabricate nanoporous polycaprolactone microtubes as potential functional capillaries. Our results showed that ambient environment parameters and solution properties affected the pore formation and tube morphology. The optimal tubular structure was obtained with consistent viscosities between the core and the sheath solutions. The biomimetic nanoporous microtubes hold great potential for vascularization in tissue engineering.application/pdfengTissue EngineeringElectrospinningVascularizationScaffoldsNanofibersThesis2021-08-17Access restricted until August 2021.