Membrane proteomics, the large-scale global analysis of membrane proteins, is often constrained by the efficiency of separating and extracting membrane proteins. Recent approaches involve conjugating membrane proteins with the small molecule biotin and using the receptor streptavidin to extract the labelled proteins. Despite the many advantages of this method, several shortcomings remain, including potential contamination by endogenously biotinylated molecules and interference by streptavidin during analytical stages. Here, we report a supramolecular fishing method for membrane proteins using the synthetic receptor-ligand pair cucurbit[7]uril-1-trimethylammoniomethylferrocene (CB[7]-AFc). CB[7]-conjugated beads selectively capture AFc-labelled proteins from heterogeneous protein mixtures, and AFc-labelling of cells results in the efficient capture of membrane proteins by these beads. The captured proteins can be recovered easily at room temperature by treatment with a strong competitor such as 1,1'-bis(trimethylammoniomethyl)ferrocene. This synthetic but biocompatible host-guest system may be a useful alternative to streptavidin-biotin for membrane proteomics as well as other biological and biotechnological applications.

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The design and synthesis of a novel reduction-sensitive, robust, and biocompatible vesicle (SSCB[6]VC) are reported, which is self-assembled from an amphiphilic cucurbit[6]uril (CB[6]) derivative that contains disulfide bonds between hexaethylene glycol units and a CB[6] core. The remarkable features of SSCB[6]VC include: 1) facile, non-destructive, non-covalent, and modular surface modification using exceptionally strong host-guest chemistry; 2) high structural stability; 3) facile internalization into targeted cells by receptor-mediated endocytosis, and 4) efficient triggered release of entrapped drugs in a reducing environment such as cytoplasm. Furthermore, a significantly increased cytotoxicity of the anticancer drug doxorubicin to cancer cells is demonstrated using doxorubicin-loaded SSCB[6]VC, the surface of which is decorated with functional moieties such as a folate-spermidine conjugate and fluorescein isothiocyanate-spermidine conjugate as targeting ligand and fluorescence imaging probe, respectively. SSCB[6]VC with such unique features can be used as a highly versatile multifunctional platform for targeted drug delivery, which may find useful applications in cancer therapy. This novel strategy based on supramolecular chemistry and the unique properties of CB[6] can be extended to design smart multifunctional materials for biomedical applications including gene delivery.

Cucurbituril-based nanoparticles (CB[6]NPs) serve as new efficient vehicles for delivery of hydrophobic drugs, which have unique features including (1) a high drug loading capacity and efficiency, (2) noncovalently tunable surfaces, (3) efficient delivery of hydrophobic drugs into a cancer cell by receptor-mediated endocytosis, and (4) facile release of drugs into cytoplasm, which enhances the pharmaceutical effects of the drugs.

Skin-like health care patches (SHPs) are next-generation health care gadgets that will enable seamless monitoring of biological signals in daily life. Skin-conformable sensors and a stretchable display are critical for the development of standalone SHPs that provide real-time information while alleviating privacy concerns related to wireless data transmission. However, the production of stretchable wearable displays with sufficient pixels to display this information remains challenging. Here, we report a standalone organic SHP that provides real-time heart rate information. The 15-μm-thick SHP comprises a stretchable organic light-emitting diode display and stretchable organic photoplethysmography (PPG) heart rate sensor on all-elastomer substrate and operates stably under 30% strain using a combination of stress relief layers and deformable micro-cracked interconnects that reduce the mechanical stress on the active optoelectronic components. This approach provides a rational strategy for high-resolution stretchable displays, enabling the production of ideal platforms for next-generation wearable health care electronics.

assistance of the positive entropy change due to the extensive dehydration of the host and guest. The high stability of the complexes allowed us and others to explore several biological applications such as immobilization of biomolecules on a solid surface, protein isolation, triggering intracellular events, and regulating enzymatic activities. These complexes with their exceptional affinity, chemical robustness, simple preparation, biocompatibility, and easy handling may replace the biotin-(strept)avidin system in diverse areas of research, including affinity chromatography, high throughput biochemical assays, imaging, and sensor technologies.

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