Material Interfaces Inspired by Catch Bond Adhesins
by Kerim Dansuk
Northwestern University, Department of Mechanical Engineering
DATE : November 25, 2022 (Friday)
TIME : 14:00-15:00
ROOM : VYKM-4
Over the last few years, there has been a transition away from traditional engineering materials to new advanced materials that exhibit complex architectures with improved mechanical properties. Most of the inspiration for these new materials comes from nature, where organisms have evolved an immense variety of macro and nanoscale shapes and structures with clever mechanisms. Adhesion proteins are particularly inspiring for novel materials because they exhibit conformational dynamics that enables them to form special non-covalent interactions called ‘catch bonds’ with their ligand, where dissociation lifetime of ligand-protein complexes is enhanced by mechanical force. Intuition suggests that application of a tensile force on a chemical bond should tend to shorten the bond’s lifetime, making it more likely to break, but catch bonds defy this notion. If implemented in material systems, catch bonds are predicted to address trade-offs between strength and reconfiguration, two diametric material properties that are primarily governed by the strength of intermolecular interactions. This work is a multifaceted approach combining molecular simulations and adhesion theory to establish strategies for designing material interfaces that incorporates catch bond features. Based on adhesin properties, we proposed design guidelines for reproducing the catch bond phenomenon in synthetic systems and created mechanical designs that mimicked protein ligand interaction and exhibited catch bond behavior reliably and predictably under thermal excitations. We demonstrate that catch bond functionality can be achieved using simple molecular mechanisms and provides design rules for making catch bond nanoparticles and linkages, which paves the way for engendering emergent force-tunable interfacial kinetics in synthetic materials.
Kerim completed his B.S. in Mechanical Engineering at Bogazici University. After finishing his PhD in Mechanical Engineering at Northwestern University, he continued to work in NU as a Postdoctoral Scholar. His research focuses on applying computational modeling and statistical thermodynamics to design procedures for nanocomposites with adhesin-inspired interfaces.