Intelligent regulation of fluid mechanical properties is an enormous challenge. Here we report a photocontrolled thermogelling system that features switchable sol–gel transition in response to light. Such a system is composed of an amphiphilic copolymer appending with charged long alkyl stickers and α-cyclodextrin (α-CD) host units. Temperature can induce reversible threading/dethreading between the α-CD and the alkyl chain, leading to a sol–gel transition. With the introduction of a competitive photoresponsive azobenzene guest, one can remotely modulate the systemic gelation points in a broad temperature window via light irradiation. This class of responsive hydrogel systems would open up a new host–guest approach for the design of logical soft materials.

Designing specific-responsive polymer nanocapsules toward a definite cell signaling molecule for targeted therapy faces a great challenge. Here we demonstrate that new block copolymer appended trifluoromethyl ketone side groups can chemoselectively respond to an endogenous redox biosignal, peroxynitrite (ONOO–), but shield the interference of other biogenic reactive oxygen, nitrogen, and sulfur species (ROS/RNS/RSS). The ONOO– signaling molecule is capable of triggering cascade oxidation–elimination reactions to cleave the side functionalities from the polymer chain, which induces a large alteration of the polymer amphiphilicity and further leads to controllable disassembly of their self-assembled vesicular structure. Modulating the ONOO– stimulus concentrations could readily control the vesicle dissociation rates for desirable drug delivery. We envisage that this polymer model would provide a new scenario to construct bioresponsive macromolecular systems for future biomedical nanotechnologies.

In this Letter, the antibacterial activities of pyridinium-tailored aromatic amphiphiles were evaluated by turbidimeter tests in vitro. The bioassays revealed that most of the target compounds exhibit appreciable inhibition activities against the plant pathogenic bacteria Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri. The half-maximal effective concentrations (EC50) of 2-NP-10, 9-AP-10, and 9-AP-7 against these three bacteria were relatively high, which may be ascribed to the favourable hydrophobicity/hydrophilicity balance in these compounds. Our results suggest that pyridinium-tailored aromatic amphiphiles are promising bactericide candidates against plant bacterial diseases.

Although a few architectures have been fabricated by the self-assembly of natural triterpenoids, the precise control of shape and size is rarely studied. Herein, a methyl oleanolate-bearing amphiphile, 1-[2-(methyl oleanolate)-2-oxoethyl]pyridinium bromide (MOP), has been designed and its assembly behavior was investigated. It was found that the morphologies of MOP assemblies ranged from nanoparticles to rigid microrods and flexible nanofibers in chloroform/p-xylene and methanol/water, respectively. During the assembly process, the systematical variational solvophobic/solvophilic effect resulted in the formation of spherical nanoparticles with opposite dipoles and converse bilayer structures. Moreover, such opposite molecular orientations lead to the inversion of supramolecular chirality and distinct mechanical properties. The driving forces and packing patterns of MOP in each solvent system were clearly demonstrated by the combination of NMR, UV–vis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), theoretical computation, and contact angle experiments, which revealed the roles of triterpenoids and pyridinium cations in the assembly process. This work provides a facile strategy to control the supramolecular structures in triterpenoid-based assemblies by adjusting the solvent polarity and composition.

A novel Zn2+ ion chemosensor 1 has been developed based on deoxycholic acid and salen motifs, and this chemosensor can be used in test-strips and living cells imaging for Zn2+ ion through a turn-on effect. Moreover, the resulting [1·Zn2+] complex exhibits turn-off response toward H2PO4− ion, thus leading to the fabrication of an INHIBIT (INH) logic gate using Zn2+ ion and H2PO4− ion as inputs and the emission of 1 as outputs, respectively. This line of research not only enriches the library of Zn2+ ion sensors, but also expands the applications of natural products-based chemosensors.A novel Zn2+ ion chemosensor 1 has been developed based on deoxycholic acid and salen motifs, and this chemosensor can be used in test-strips and living cells imaging for Zn2+ ion through a turn-on effect. Moreover, the resulting [1·Zn2+] complex exhibits turn-off response toward H2PO4− ion, leading to the fabrication of an INHIBIT (INH) logic gate using Zn2+ ion and H2PO4− ion as inputs and the emission of 1 as outputs, respectively. This line of research not only enriches the library of Zn2+ ion sensors, but also expands the applications of natural products-based chemosensors.

Host–guest interactions are employed to manipulate the assembled morphology of an amphiphile, 2-NP, which contains an electron-rich naphthalene group and an electron-deficient pyridinium cation linked with a flexible alkyl arm. By encapsulating the pyridinium and the naphthalene group of 2-NP into the cavity of cucurbit[8]uril (CB[8]), fluorescence-enhanced microsheets were formed.

Host–guest interactions are employed to manipulate the assembled morphology of an amphiphile, 2-NP, which contains an electron-rich naphthalene group and an electron-deficient pyridinium cation linked with a flexible alkyl arm. By encapsulating the pyridinium and the naphthalene group of 2-NP into the cavity of cucurbit[8]uril (CB[8]), fluorescence-enhanced microsheets were formed.