Danyu Xia

A Dual-Responsive Supra-Amphiphilic Polypseudorotaxane Constructed from a Water-Soluble Pillar[7]arene and an Azobenzene-Containing Random Copolymer

Macromolecular supra-amphiphiles refer to a kind of macromolecular amphiphiles whose hydrophlic and hydrophobic parts are connected by noncovalent forces. They have applications in various fields, such as drug delivery, sensor systems, and biomedical materials. Here we report a novel molecular recognition motif between a new thermoresponsive water-soluble pillar[7]arene (WP7) and an azobenzene derivative. Furthermore, we utilized this recognition motif to construct the first pillararene-based supra-amphiphilic polypseudorotaxane which can self-assemble to form vesicles in water. Due to the dual-responsiveness of the molecular recognition motif (the thermoresponsiveness of WP7 and photoresponsiveness of azobenzene), the reversible transformations between solid nanospheres based on the self-assembly of the polymer backbone and vesicles based on the self-assembly of the supra-amphiphilic polypseudorotaxane were achieved by adjusting the solution temperature or UV-visible light irradiation. These dual-responsive aggregation behaviors were further used in the controlled release of water-soluble dye calcein molecules.

A Novel Diblock Copolymer with a Supramolecular Polymer Block and a Traditional Polymer Block: Preparation, Controllable Self-Assembly in Water, and Application in Controlled Release

A novel diblock copolymer with a hydrophobic supramolecular polymer block and a hydrophilic traditional polymer block has been prepared. Control over the chain length ratio of the two blocks is obtained by simply changing the concentration proportion of the monomer of the supramolecular polymer block to the traditional polymer block in solution. When the chain length ratio of the two blocks is changed, the formation of various self-assembly morphologies is achieved.

Nanoparticles with Near-Infrared Emission Enhanced by Pillararene-Based Molecular Recognition in Water

Here we report the unprecedented preparation of nanoparticles with near-infrared (NIR) emission enhanced by host-guest complexation between a water-soluble pillar[5]arene (WP5) and a cyanostilbene derivative (1) in water. Amphiphilic 1 self-assembles in water to form nanoribbons with relatively weak NIR emission at low concentrations. However, after addition of equimolar WP5, these nanoribbons transform into nanoparticles with stronger NIR emission due to the formation of a supramolecular amphiphile and host-guest complexation-enhanced aggregation. These nanoparticles show pH responsiveness, and collapse after treatment with acid. More importantly, these nanoparticles can be used in living cell imaging.

Supramolecular Construction of Multifluorescent Gels: Interfacial Assembly of Discrete Fluorescent Gels through Multiple Hydrogen Bonding.

Multifluorescent supramolecular gels with complex structures are constructed from discrete fluorescent gels, which serve as the building blocks, through hydrogen bonding interactions at interfaces. The multifluorescent gel can realize rapid healing within only ≈100 s.

An enzyme-responsive supra-amphiphile constructed by pillar[5]arene/acetylcholine molecular recognition

A novel molecular recognition motif between a water-soluble pillar[5]arene (WP5) and acetylcholine is established with an association constant of (5.05 ± 0.13) × 104 M−1. Based on this molecular recognition motif, an enzyme-responsive supra-amphiphile is constructed by introducing an amphiphilic guest (PyCh) that is sensitive to acetylcholinesterase. Furthermore, supramolecular hybrid materials are prepared by introducing gold nanoparticles (AuNPs) into these supramolecular systems, which show enzyme-responsive catalytic abilities for the borohydride reduction of 4-nitroaniline.

A supramolecular polymer network gel with stimuli-responsiveness constructed by orthogonal metal ion coordination and pillar[5]arene-based host–guest recognition

A novel external stimuli-responsive supramolecular metallogel was fabricated by orthogonal Ag-coordination and pillar[5]arene-based host–guest molecular recognition.

A Water-Soluble Cyclotriveratrylene-Based Supra-amphiphile: Synthesis, pH-Responsive Self-Assembly in Water, and Its Application in Controlled Drug Release

A new water-soluble cyclotriveratrylene (WCTV) was designed and synthesized, and benzyldimethyldodecylammonium chloride (G) was chosen as the guest molecule to construct a supra-amphiphile by the host-guest interaction between WCTV and G in water, which is pH responsive. The supra-amphiphiles self-assembled into vesicles in water. When the pH of the solution was below 7.0, the supra-amphiphile disassociated, and the vesicles collapsed. Then, the pH-responsive self-assembly system was utilized for controlled drug release.

Dual-responsive self-assembly of a bola-type supra-amphiphile constructed from a new pillar[6]arene-based recognition motif in water and its application in controlled release

Dual-responsive self-assembly of a bola-type supra-amphiphile was constructed from a new recognition motif based on a water-soluble pillar[6]arene and an azobenzene-containing guest in water and its application in controlled release was studied.

A pillar[5]arene-based 3D network polymer for rapid removal of organic micropollutants from water

Organic micropollutants are posing great challenges to global water resources, especially for non-biodegradable synthetic chemicals. In this study, a carboxyl-derived pillar[5]arene (P5) and p-phenylenediamine (PPD) were crosslinked to produce a 3D network polymer, P5-P, for the adsorption and removal of organic micropollutants from water. This 3D network polymer sequesters a variety of organic micropollutants in water with rapid adsorption rates and large uptake amounts, much greater than those of conventional activated carbon. Especially, this polymer demonstrates superior adsorption performance for fluorescein sodium and methyl orange and it can be fully regenerated multiple times by a mild washing procedure. The structure of this 3D network polymer and its adsorption mechanisms have been confirmed by solid-state nuclear magnetic resonance (SSNMR). The excellent pollutant removal ability demonstrates the promise of the pillar[5]arene-based 3D network polymer for rapid waste-water treatment.