A supramolecular assembly strategy towards organic luminescent materials

Supramolecular organic luminescent materials with different dimensionalities usually exhibit different optical properties as well as their potential applications in various fields. Recent reports showed that non-covalent interactions are useful tools to obtain diverse luminescent materials due to their dynamicity and reversibility, including π-π stacking, host-guest interactions, hydrophobic effects, hydrogen bonding, electrostatic effects and so on. In this review, we summarized recent progress in zero-, one-, two-, three-dimensional and disordered organic luminescent materials using the aforementioned strategies, in order to provide a solution for designing luminescent materials with specific structures and morphologies. The relationship between assembly behavior and luminescent properties is discussed in detail, along with the existing difficulties hindering the development of supramolecular assembly systems and future research directions.

Supramolecular Organic Frameworks: Exploring Water-Soluble, Regular Nanopores for Biomedical Applications

In past decades, regular porous architectures have received a great amount of attention because of their versatile functions and applications derived from their efficient adsorption of various guests. However, most reported porous architectures exist only in the solid state. Therefore, their applications as biomaterials may face several challenges, such as phase separation, slow degradation, and long-term accumulation in the body. This Account summarizes our efforts with respect to the development and biomedical applications of water-soluble 3D diamondoid supramolecular organic frameworks (dSOFs), a family of supramolecular polymers that possess intrinsic regular nanoscale porosity.dSOFs have been constructed from tetratopic components and cucurbit[8]uril (CB[8]) through hydrophobically driven encapsulation by CB[8] for intermolecular dimers formed by peripheral aromatic subunits of the tetratopic components in water. All dSOFs exhibit porosity regularity or periodicity in aqueous solution, which is confirmed by solution-phase synchrotron SAXS and XRD experiments. Dynamic light scattering (DLS) reveals that their sizes range from 50 to 150 nm, depending on the concentrations of the components. As nonequilibrium supramolecular architectures, dSOFs can maintain their nanoscale sizes at micromolar concentrations for dozens of hours. Their diamondoid pores have aperture sizes ranging from 2.1 to 3.6 nm, whereas their water solubility and porosity regularity allow them to rapidly include discrete guests driven by ion-pair electrostatic attraction, hydrophobicity, or a combination of the two interactions. The guests may be small molecule or large macromolecular drugs, photodynamic agents (PDAs), or DNA.The rapid inclusion of bioactive guests into dSOFs has led to two important biofunctions. The first is to function as antidotes through including residual drugs. For heparins, the inclusion results in full neutralization of their anticoagulant activity. For clinically used porphyrin PDAs, the inclusion can alleviate their long-term posttreatment phototoxicity but does not reduce their photodynamic efficacy. The second is to function as in situ loading carriers for the intracellular delivery of antitumor drugs or DNA. Their nanoscale sizes bring out their ability to overcome the multidrug resistance of tumor cells, which leads to a remarkable enhancement of the bioactivity of the included drugs. By conjugating aldoxorubicin to tetrahedral components, albumin-mimicking prodrugs have also been constructed, which conspicuously improves the efficacy of aldoxorubicin toward multi-drug-resistant tumors through the delivery of the frameworks. As new supramolecular drugs and carriers, dSOFs are generally biocompatible. Thus, further efforts might lead to medical benefits in the future.