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Colloidal chirality in wormlike micellar systems exclusively originated from achiral species and discussion of the role of secondary assembly of fiber-like aggregates in chirality generation were presented in this paper. Herein, formation of colloidal wormlike micelles for the first time incorporated chirality and redox-responsiveness into one design via noncovalent interaction. A dual-stimuli-responsive gel of wormlike micelles which were designed by employing a dual-responsive cationic surfactant (FTMA) and a strong gelator (AzoNa 4 ) and regulated by redox reaction and host-guest inclusion is presented. Both the redox and host-guest interaction play an important role in regulating the viscosity and supramolecular chirality of gels of the wormlike micelles. The supramolecular chirality and viscosity of the wormlike micelle gels were switched reversibly by exerting chemical redox onto the ferrocenyl groups. For the amphiphile FTMA containing redox-active ferrocenyl group, reversible control of the oxidation state of ferrocenyl groups leads to the charge and hydrophobicity changes of FTMA, therefore change its self-assembly behavior. Of equal interest, β-CD successfully detached the wormlike micelles via the recognition-inclusion behavior with FTMA and invalidate the H-bond and hydrophobic interaction between FTMA and AzoH 4 . This designed system provides a new strategy to tune the supramolecular chirality of colloidal aggregates and explore the specific packing mode detail within the micelles or the secondary assembly of the inter-micelles. We anticipate this dual-responsive H-bond-directed chiral gel switch could propose a new strategy when researchers designing new, multi-responsive functional gel materials. [ABSTRACT FROM AUTHOR]

A multiresponsivehydrogel material consisting of a commercialcationic surfactant and an azobenzene derivative functionalized withfour carboxylic acid groups was constructed. The achiral azobenzenemolecule as a gelator produces chirality at the supramolecular levelin the presence of H+. The acid-induced gelation and morphologychange of supramolecular gels were investigated in detail by cryogenictransmission electron microscopy (cryo-TEM), rheological measurements,circular dichroism (CD), and 1H NMR spectra. Based on theresults, a mechanism of the intermolecular H-bond-directed gelationand supramolecular chirality was proposed. Other than the pH sensitivity,the microstructure and the chirality of the hydrogel demonstrate reversibleswitching behavior in response to photoirradiation, on account ofthe photoisomerization of the azobenzene derivative. Accordingly,a chiroptical switch comprising four different states in responseto pH and light stimuli is strategically constructed. Not only doesthe present system provide a good opportunity for investigating thegelation-induced supramolecular chirality by symmetry breaking totallybased on achiral molecules, but it also proposes a new strategy tobuild multiresponsive supramolecular switches as particularly attractivefor the future development of functional materials. [ABSTRACT FROM AUTHOR]