The Polymer and Fiber Engineering Department
Announces a Presentation by

Abby R. Whittington, PhD
Department of Materials Science and Engineering
Department of Chemical Engineering
Virginia Tech
Blacksburg, VA

"Fabrication of a continuously graded co-electrospun mesh to mimic
the ligament-bone interface"

Current scaffolds for the regeneration of anterior cruciate ligament injuriesare unable to capture intricate mechanical and chemical gradients present inthe natural ligament‐bone interface. As a result, stress concentrations candevelop at the scaffold‐bone interface, leading to poor osseointegration. Hence,scaffolds that possess appropriate mechano‐chemical gradients would helpestablish normal loading properties at the interface, while promoting scaffoldintegration with bone. Thus, the aim of this study was to fabricate acontinuously graded mesh with the long‐term goal of regenerating theligament‐bone interface. Specifically, graded meshes were fabricated by coelectrospinningnano‐hydroxyapatite/polycaprolactone (nHAP‐PCL) andpoly‐(ester urethane) urea elastomer solutions from offset spinnerets. Next,mineral crystallites were selectively deposited on the nHAP‐PCL fibers bytreatment with a 5x simulated body fluid (5xSBF). X‐ray diffraction andenergy dispersive spectroscopy indicated calcium deficient hydroxyapatitelikemineral crystallites with an average Ca/P ratio of 1.48. Tensile testingdemonstrated the presence of a mechanical gradient, which became morepronounced upon treatment with 5xSBF. Finally, biocompatibility of thegraded meshes was verified using a MC3T3‐E1 osteoprogenitor cell line. Thestudy demonstrates that graded meshes, for potential application ininterfacial tissue engineering, can be fabricated by co‐electrospinning.

Tuesday, April 26, 2011 - 2:00-3:00 pm
Room 104 Textile Engineering Building
Refreshments will be served 15 minutes prior to each seminar