Cyclodextrins (CDs), which are a class of cyclic oligosaccharides extracted from the enzymatic degradation of starch, are often utilized in molecular recognition and assembly constructs, primarily via host–guest interactions in water. In this review, recent progress in CD‐based supramolecular nanoassemblies that are sensitive to chemical, biological, and physical stimuli is updated and reviewed, and intriguing examples of the biological functions of these nanoassemblies are presented, including pH‐ and redox‐responsive drug and gene delivery, enzyme‐activated specific cargo release, photoswitchable morphological interconversion, microtubular aggregation, and cell–cell communication, as well as a geomagnetism‐controlled nanosystem for the suppression of tumor invasion and metastasis. Moreover, future perspectives and challenges in the fabrication of intelligent CD‐based biofunctional materials are also discussed at the end of this review, which is expected to promote the translational development of these nanomaterials in the biomedical field.

Cucurbit[n]urils (Q[n]s or CB[n]s), as a classical of artificial organic macrocyclic hosts, were found to have excellent advantages in the fabricating of tunable and smart organic luminescent materials in aqueous media and the solid state with high emitting efficiency under the rigid pumpkin-shaped structure-derived macrocyclic-confinement effect in recent years. This review aims to give a systematically up-to-date overview of the Q[n]based supramolecular organic luminescent emissions from the confined spaces triggered host−guest complexes, including the assembly fashions and the mechanisms of the macrocycle-based luminescent complexes, as well as their applications. Finally, challenges and outlook are provided. Since this class of Q[n]-based supramolecular organic luminescent emissions, which have essentially derived from the cavity-dependent confinement effect and the resulting assembly fashions, emerged only a few years ago, we hope this review will provide valuable information for the further development of macrocycle-based light-emitting materials and other related research fields.

Recently, the gut microbiota (GM) has been shown to be a regulator of bone homeostasis and the mechanisms by which GM modulates bone mass are still being investigated. Here, it is found that colonization with GM from children (CGM) but not from the elderly (EGM) prevents decreases in bone mass and bone strength in conventionally raised, ovariectomy (OVX)‐induced osteoporotic mice. 16S rRNA gene sequencing reveals that CGM reverses the OVX‐induced reduction of Akkermansia muciniphila (Akk). Direct replenishment of Akk is sufficient to correct the OVX‐induced imbalanced bone metabolism and protect against osteoporosis. Mechanistic studies show that the secretion of extracellular vesicles (EVs) is required for the CGM‐ and Akk‐induced bone protective effects and these nanovesicles can enter and accumulate into bone tissues to attenuate the OVX‐induced osteoporotic phenotypes by augmenting osteogenic activity and inhibiting osteoclast formation. The study identifies that gut bacterium Akk mediates the CGM‐induced anti‐osteoporotic effects and presents a novel mechanism underlying the exchange of signals between GM and host bone.

Direct growth of single-walled carbon nanotubes (SWNTs) on flat substrates by chemical vapor deposition (CVD) is very important for the application of SWNTs in nanodevices. In the growth process, catalysts play an important role in controlling the structure of SWNTs. Over the years, we have systematically studied the size-controlled synthesis of Fe-based nanoparticles and the CVD growth of SWNTs, especially the horizontally aligned SWNTs, catalyzed by these produced nanoparticles. Some new catalysts were also developed. Among them, Cu is shown to be a superior catalyst for growing SWNT arrays on both silicon and quartz substrates and Pb is a unique catalyst from which one can obtain SWNTs without any metallic contaminant. SWNTs prepared with both Cu and Pb are very suitable for building high-performance nanodevices. These studies are also very helpful for further understanding the growth mechanism of SWNTs.

The experimental detection and synthesis of pentazole (HN ) and its anion (cyclo-N ) have been actively pursued for the past hundred years. The synthesis of an aesthetic three-dimensional metal-pentazolate framework (denoted as MPF-1) is presented. It consists of sodium ions and cyclo-N anions in which the isolated cyclo-N anions are preternaturally stabilized in this inorganic open framework featuring two types of nanocages (Na N and Na N ) through strong metal coordination bonds. The compound MPF-1 is indefinitely stable at room temperature and exhibits high thermal stability relative to the reported cyclo-N salts. This finding offers a new approach to create metal-pentazolate frameworks (MPFs) and enables the future exploration of interesting pentazole chemistry and also related functional materials.

A multiple supramolecular assembly, in which a folic acid-modified β-cyclodextrin (1) acted as a target unit, an adamantanyl porphyrin (2) acted as a linker unit, and graphene oxide acted as a carrier unit, was successfully fabricated through non-covalent interactions and comprehensively investigated by means of UV/Vis, fluorescence, and X-ray photoelectron spectroscopies, and electron microscopy. Significantly, the graphene oxide unit could associate with the anticancer drug doxorubicin through π-π interactions, and the folic acid-modified β-cyclodextrin unit could recognize the folic acid receptors in cancer cells. Owing to the cooperative contribution of these three units, the resulting multiple supramolecular assembly, after association with doxorubicin, exhibited better drug activity and much lower toxicity than free doxorubicin in vivo.

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