Light-induced dynamic shaping and self-division of multipodal polyelectrolyte-surfactant microarchitectures via azobenzene photomechanics

• DOI: 10.1038/srep41327
• Publication Date: 2017-01-23T12:10:13Z
• Authors: Nicolas Martin; Kamendra P. Sharma; Robert L. Harniman; Robert M. Richardson; Ricky J. Hutchings; Dominic Alibhai; Mei Li; Stephen Mann
• Keywords: Molecular-Motion; Water; 500; Amphiphiles; 02 engineering and technology; /dk/atira/pure/core/keywords/biodesign_SRI; 540; Crystals; 01 natural sciences; Article; 0104 chemical sciences; SYNTHETIC BIOLOGY; Photomobile Polymer Materials; Complexes; Transition; Irradiation; Photoirradiation; name=Bristol BioDesign Institute; /dk/atira/pure/core/keywords/biodesign_SRI; name=Bristol BioDesign Institute; Mechanical Motion; 0210 nano-technology

AbstractLight-induced shape transformations represent a fundamental step towards the emergence of adaptive materials exhibiting photomechanical behaviours. Although a range of covalent azobenzene-based photoactive materials has been demonstrated, the use of dynamic photoisomerization in mesostructured soft solids involving non-covalent co-assembly has received little attention. Here we prepare discrete micrometre-sized hydrated particles of a hexagonally ordered polyelectrolyte-surfactant mesophase based on the electrostatically induced co-assembly of poly(sodium acrylate) (PAA) and trans-azobenzene trimethylammonium bromide (trans-azoTAB), and demonstrate unusual non-equilibrium substrate-mediated shape transformations to complex multipodal microarchitectures under continuous blue light. The microparticles spontaneously sequester molecular dyes, functional enzymes and oligonucleotides, and undergo self-division when transformed to the cis state under UV irradiation. Our results illustrate that weak bonding interactions in polyelectrolyte-azobenzene surfactant mesophases can be exploited for photo-induced long-range molecular motion, and highlight how dynamic shape transformations and autonomous division can be activated by spatially confining azobenzene photomechanics in condensed microparticulate materials.