Liulin Yang

Supramolecular Polymerization Promoted and Controlled through Self‐Sorting

A new method in which supramolecular polymerization is promoted and controlled through self-sorting is reported. The bifunctional monomer containing p-phenylene and naphthalene moieties was prepared. Supramolecular polymerization is promoted by selective recognition between the p-phenylene group and cucurbit[7]uril (CB[7]), and 2:1 complexation of the naphthalene groups with cucurbit[8]uril (CB[8]). The process can be controlled by tuning the CB[7] content. This development will enrich the field of supramolecular polymers with important advances towards the realization of molecular-weight and structural control.

Supramolecular polymer fabricated by click polymerization from supramonomer

In contrast with macromonomer in traditional polymer science, supramonomer refers to a monomer that is fabricated by noncovalent interactions, but is able to polymerize using conventional methods of polymerization. This communication describes the fabrication of a supramonomer based on supramolecular complexation between cucurbit[8]uril and the tripeptide Phe-Gly-Gly derivative. The supramolecular polymer is obtained by click polymerization of the supramonomer. It is expected that this line of research will provide a new method for fabricating supramolecular polymers.

Water-soluble supramolecular polymers fabricated through specific interactions between cucurbit[8]uril and a tripeptide of Phe-Gly-Gly

A bifunctional monomer FGG-PEG8-GGF bearing two Phe-Gly-Gly residues and an octaethylene glycol linker has been designed and synthesized. Water-soluble supramolecular polymers can form spontaneously by mixing the monomer and cucurbit[8]uril (CB[8]) in a 1 : 1 ratio through specific interactions between CB[8] and the Phe-Gly-Gly residues.

Supramolecular polymerization of supramonomers: a way for fabricating supramolecular polymers

This communication describes a new method of fabricating supramolecular polymers through supramolecular polymerization of supramonomers. To mix building blocks of Phe-Gly-Gly linked with an azobenzene group and cucurbit[8]uril (CB[8]) in a molar ratio of 2 : 1 in aqueous solutions, supramonomers were obtained by host–guest interaction between tripeptide and CB[8]. Then supramolecular polymers were formed spontaneously by mixing the supramonomers with bis-β-cyclodextrins in a molar ratio of 1 : 1 in an aqueous solution through noncovalent host–guest complexation of the azobenzene group and β-cyclodextrin. Considering that various noncovalent interactions can be used to drive the formation of supramonomers and the supramolecular polymerization of the supramonomers, this study can enrich the methodology of fabricating supramolecular polymers.

Supramolecular glycolipid based on host-enhanced charge transfer interaction.

Supramolecular glycolipid has been fabricated based on ternary complex system, which is composed of naphthyl glucosamine (GlcNap), alkyl viologen (RV8), and cucurbit[8]uril (CB[8]). CB[8] plays a key role to connect the other two building blocks together, and the process is driven by host-enhanced charge transfer interaction. Compared with the classic glycolipids, supramolecular glycolipids display redox responsiveness. Supramolecular glycolipids are able to self-assemble in water to form spherical aggregations, such as vesicle like structure. In addition, spherical aggregations can specifically interact with Concanavalin A, indicating that the carbohydrate groups are available on the surfaces of the aggregates.

Rational Adjustment of Multicolor Emissions by Cucurbiturils-Based Host–Guest Chemistry and Photochemistry

The host-guest chemistry of cucurbiturils and the photochemistry of azastilbene derivatives are combined for the rationally adjusting multicolor emissions through forming different host-guest complexes and their corresponding photochemical products. Cucurbit[8]uril (CB[8]) can bind with azastilbene derivatives to form supramolecular polymers emitting orange light. The supramolecular polymers further facilitate the [2 + 2] cycloaddition of C═C bonds in azastilbenes by UV irradiation, emitting blue light. Different from CB[8], cucurbit[7]uril (CB[7]) encapsulates azastilbene derivatives to form a dumbbell-shaped host-guest complex, emitting dark-purple light. This dumbbell-shaped host-guest complex undergoes cis-isomerization after UV irradiation, thus emitting green light. Therefore, this strategy is promising for fabricating advanced stimuli-responsive fluorescent materials.

Amphiphilic diselenide-containing supramolecular polymers

This communication describes the fabrication of diselenide-containing supramolecular polymers. The diselenide-containing supramolecular polymers were fabricated by equimolarly mixing (FGGC11Se)2 and CB[8] in aqueous solution driven by host–guest interactions between cucurbit[8]uril (CB[8]) and Phe-Gly-Gly. The amphiphilic diselenide-containing supramolecular polymers could further form aggregates for loading hydrophobic small molecules such as Nile Red and releasing them upon addition of oxidants or reductants. This line of research not only expands the library of selenium-containing polymers, but also offers a new strategy to develop functional supramolecular polymers for drug delivery.

Reactive oxygen species (ROS)-responsive tellurium-containing hyperbranched polymer

Materials responsive to reactive oxygen species (ROS) at a physiological level are of great significance in diagnostic and therapeutic applications. We have synthesized a water-soluble tellurium-containing hyperbranched polymer and demonstrated that it forms a kind of ROS-responsive aggregate. In aqueous environment, the polymer aggregates can swell under biologically relevant concentration of H2O2, which could be expected to find applications in fields such as elimination of excess ROS.

Supra-amphiphiles formed by complexation of azulene-based amphiphiles and pyrene in aqueous solution: from cylindrical micelles to disklike nanosheets

We have fabricated supra-amphiphiles by charge-transfer complexation of azulene-based amphiphiles and pyrene in water, and the self-assembled nanostructures can reversibly change between cylindrical micelles and disklike nanosheets in response to interaction with guest molecules.

Supramolecular polymers synthesized by thiol–ene click polymerization from supramonomers

This communication describes the fabrication of supramonomers based on supramolecular complexation between cucurbit[8]uril and the tetrapeptide Phe-Gly-Gly-Cys. The supramolecular polymers are obtained by thiol–ene click polymerization of the supramonomers with maleimide-terminated poly(ethylene glycol). Benefiting from the green and pH dependent nature of thiol–ene click reaction, it is expected that this line of research will enrich the methodology for fabricating supramolecular polymers with controlled compositions and structures.