Hierarchical "As-Electrospun" Self-Assembled Fibrous Scaffolds Deconvolute Impacts of Chemically Defined Extracellular Matrix- and Cell Adhesion-Type Interactions on Stem Cell Haptokinesis.

Controlled self-assembly of diblock copolymers offers the possibility of fabricating multilength scale, three-dimensional (3D) porous/fibrous structures (or scaffolds) with defined internal nano- or microstructure, with opportunities for application in a variety of fields, ranging from energy storage to bioengineering. Traditional methods by which such 3D constructs are produced are time-consuming and tedious, hindering their broader exploitation within larger-scale industrial processes. We report the development of a one-step process to fabricate "as-electrospun" self-assembled diblock copolymer micro- to nanometer-sized fibers incorporating core-shell or lamellar, closely packed spheres or bicontinuous gyroid nanosized structures. Isotropic and anisotropic (aligned) porous mats presenting spatially controlled chemistries, including bioactive (peptide-based) motifs, were successfully made from these hierarchical fibers. When functionalized with peptide sequences derived from a cell adhesion molecule ( E -cadherin) and an extracellular matrix glycoprotein (laminin), these novel materials provided new insight into the impacts of such exquisitely tailored contact-guidance cues on the haptokinesis of human mesenchymal stem cells.