Mesoscopic Supramolecular Assembly of Stereolithographically Printed Microgels

Abstract

Microgels that assemble upon issuing of a trigger open up miscellaneous applications in soft robotics, drug delivery, and life-like materials, due to their unique physical and chemical properties. In this work, a novel hydrogel photoresist system is formulated, consisting of 2-hydroxyethyl acrylate, ethylene glycol diacrylate, and phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide, as well as redox-sensitive supramolecular host-guest association motifs. Complex and multi-compartmented geometries with precisely located recognition motifs are printed in high resolution, resulting in multifunctional structured microgel building blocks for mesoscopic self-assembly. An enzymatic feedback system is employed to dissipatively assemble and disassemble the redox-active microgel building blocks in a temporally and spatially controlled pathway. The self-assembling photoresist system is characterized in terms of the lower critical solution temperature, swelling behavior, and printability. The present work provides new perspectives for the design of tailor-made mesoscopic microgels with customizable functionality and high applicability for various technological applications.