Elastomeric Electrospun Polyurethane Scaffolds: The Interrelationship Between Fabrication Conditions, Fiber Topology, and Mechanical Properties
Electrospinning has been gaining increasing popularity in the fabrication of engineered tissue scaffolds due to its ability to produce nano to micro scale fibrous sheets. Many investigators have attempted to apply various degrees of control to this process in order to produce fiber meshes with more predictable patterns. These attempts have largely been limited to controlling fiber alignment and have fallen into two categories: physical manipulation of the fibers by pulling them into alignment using a rapidly spinning mandrel[1–3] or manipulation of the electric field during fabrication.[4, 5]
Nonthrombogenic, Biodegradable Elastomeric Polyurethanes with Variable Sulfobetaine Content
For applications where degradable polymers are likely to have extended blood contact, it is often important for these materials to exhibit high levels of thromboresistance. This can be achieved with surface modification approaches, but such modifications may be transient with degradation. Alternatively, polymer design can be altered such that the bulk polymer is thromboresistant and this is maintained with degradation. Toward this end a series of biodegradable, elastic polyurethanes (PESBUUs) containing different zwitterionic sulfobetaine (SB) content were synthesized from a polycaprolactone-diol (PCL-diol):SB-diol mixture (100:0, 75:25, 50:50, 25:75 and 0:100) reacted with diisocyanatobuta…
Microstructural manipulation of electrospun scaffolds for specific bending stiffness for heart valve tissue engineering
Biodegradable thermoplastic elastomers are attractive for application in cardiovascular tissue construct development due to their amenability to a wide range of physical property tuning. For heart valve leaflets, while low flexural stiffness is a key design feature, control of this parameter has been largely neglected in the scaffold literature where electrospinning is being utilized. This study evaluated the effect of processing variables and secondary fiber populations on the microstructure, tensile and bending mechanics of electrospun biodegradable polyurethane scaffolds for heart valve tissue engineering. Scaffolds were fabricated from poly(ester urethane) urea (PEUU) and the deposition…