Mechano-Responsive Colloidal Gels

Prof. Dr. Andrij Pich, RWTH Aachen – Leibnitz-Institut für Interaktive Materialen, Aachen

Mechanical forces play important role in biological processes influencing the structure and function of organisms at various levels – from cellular to organ systems. These forces play essential roles in a range of biological functions, including tissue development, wound healing, cell signaling, and the maintenance of homeostasis. Soft biological tissues are composed of macromolecular and low-molecular components, containing covalent and non-covalent crosslinks, and are assembled in a modular way exhibiting different hierarchy levels. Such hydrogel-like materials often exhibit hysteresis effects and non-linearity of their mechanical properties, which is essential to functions like adaptability and time-programming.
Aqueous colloidal gels serve as model systems to understand many fundamental aspects of the mechano-chemistry, mechano-responsiveness and mechano-actuation because their properties can be tailored by precision synthesis methods and they can be used as colloidal building blocks to fabricate hierarchically structured soft materials in a modular way.
This presentation will focus on chemical design of mechano-responsive colloidal gels and their behavior in force fields. Synthesis approaches to obtain mechano-responsive colloidal gels exhibiting weak covalent (disulfide, diselenide) and non-covalent (host-guest complexes, ionic bonds or hydrogen bonds) crosslinks will be described.Upon application of mechanical force colloidal gels show interesting properties like on-demand degradation, reinforcement, radical scavenging and controlled release of biomolecules