Synthetic stimuli responsive supramolecular polymers attract increasing interest for their ability to mimic the unique properties of natural assemblies. Here we focus on the well-studied benzene-1,3,5-tricarboxamide (BTA) motif, and substitute it with two (S)-3,7-dimethyloctyl groups and an azobenzene photoswitch. We demonstrate the UV (λ=365 nm) induced depolymerisation of the helical hydrogen-bonded polymers in methylcyclohexane (MCH) through circular dichroism and UV-vis spectroscopy in dilute solution (15 μm), and NMR and iPAINT super-resolution microscopy in concentrated solution (300 μm).
View Article and Find Full Text PDFOne of the most appealing features of supramolecular assemblies is their ability to respond to external stimuli due to their noncovalent nature. This provides the opportunity to gain control over their size, morphology, and chemical properties and is key toward some of their applications. However, the design of supramolecular systems able to respond to multiple stimuli in a controlled fashion is still challenging.
View Article and Find Full Text PDFEngineered living materials have the potential for wide-ranging applications such as biosensing and treatment of diseases. Programmable cells provide the functional basis for living materials; however, their release into the environment raises numerous biosafety concerns. Current designs that limit the release of genetically engineered cells typically involve the fabrication of multilayer hybrid materials with submicrometer porous matrices.
View Article and Find Full Text PDFMacromol Rapid Commun
December 2014
Hierarchical self-assembly of transient composite hydrogels is demonstrated through a two-step, orthogonal strategy using nanoparticle tectons interconnected through metal-ligand coordination complexes. The resulting materials are highly tunable with moduli and viscosities spanning many orders of magnitude, and show promising self-healing properties, while maintaining complete optical transparency.
View Article and Find Full Text PDFThis paper presents a novel surface engineering approach that combines photochemical grafting and surface-initiated atom transfer radical polymerization (SI-ATRP) to attach zwitterionic polymer brushes onto indium tin oxide (ITO) substrates. The photochemically grafted hydroxyl-terminated organic layer serves as an excellent platform for initiator attachment, and the zwitterionic polymer generated via subsequent SI-ATRP exhibits very good antifouling properties. Patterned polymer coatings can be obtained when the surface with covalently attached initiator was subjected to photomasked UV-irradiation, in which the C-Br bond that is present in the initiator was broken upon exposure to UV light.
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