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Despite the recent development of highly efficient and stable metal catalysts, conferral of regulatory characteristics to the catalytic reaction in heterogeneous systems remains a challenge. Novel supramolecular nanotubules were prepared by alternative stacking from trimeric macrocycles, which was found to be able to coordinate with Pd cations. The Pd complexes exhibited a high catalytic performance for C-C coupling reaction. Notably, the tubular catalyst was observed to be controlled by supramolecular reversible assembly and showed superior heterogeneous catalytic activity, which was maintained for a number of cycles or reuse under an aerobic environment. Furthermore, the supramolecular catalyst showed unprecedented selectivity for the multifunctional coupling reaction and was able to serve as a new constructor of asymmetrical compounds.

Flap endonuclease 1 (FEN1), an endogenous nuclease with the ability to cleave the 5′ overhang of branched dsDNA, is of significance in DNA replication and repair. The overexpression of FEN1 is common in cancer because of the ubiquitous upregulation of DNA replication; thus, FEN1 has been recognized as a potential biomarker in oncological investigations. However, few analytical methods targeting FEN1 with high sensitivity and simplicity have been developed. This work developed a signal-amplified detection of FEN1 based on the cleavage-induced ligation of a dumbbell DNA probe and rolling circle amplification (RCA). A flapped dumbbell DNA probe (FDP) was rationally designed with a FEN1 cleavable flap at the 5′ end. The cleavage generated a nick site with juxtaposed 5′ phosphate and 3′ hydroxyl ends, which were linkable by T4 DNA ligase to form a closed dumbbell DNA probe (CDP) with a circular conformation. The CDP functioned as a template for RCA, which produced abundant DNA that could be probed using SYBR Green I. The highly sensitive detection of FEN1 with a limit of detection of 15 fM was achieved, and this method showed high specificity, which enabled the quantification of FEN1 in real samples. The inhibitory effects of chemicals on FEN1 were also evaluated. This study represents the first attempt to develop an FEN1 assay that involves signal amplification, and the novel biosensor method enriches the tools for FEN1-based diagnostics.

Despite recent advances in the porous materials for efficient removal of dissolved organic pollutants from water, the regeneration of porous characteristics for reuse with preventing secondary contamination remains a challenge. Here, novel supramolecular absorbents with hydrophobic pore are prepared by the self-assembly of propeller-shaped aromatic amphiphiles. The assembly of folded propeller provides a mesoporous environment within aromatic segments, which is suitable for the removal of organic pollutants from waste water. The removal efficiency is found to be 92% and 90% for ethinyl oestradiol (Eo) and bisphenol A (BPA). Notably, the folded architecture of propeller is observed to be flattened by the salt addition, which results in the strong π-π interaction driving the porous materials closed and forms solid fibers. It is found that most of the removed pollutants are spontaneously released by the dynamic porous assembly, and subsequent dialysis triggers the porous materials to be recovered.

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