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Natural products often contain a large number of structurally similar compounds, however, from which the isolation of monomer compounds is complex and time-consuming. In this study, for the first time, a Zr-based metal-organic framework (MOF), UiO-66, was used for the separation of three isoflavones (genistein (GEN), puerarin (PUE), and daidzein (DDZ)) with similar structures. UiO-66 was demonstrated to have a distinct high adsorption capacity (q e , 105.42 ± 2.36 mg/g) for GEN with high separation factors from PUE (α, 35.52 ± 1.22) and DDZ (α, 7.41 ± 0.76), dramatically increasing the purity of GEN from ∼33–92% after primary separation. According to SEM-EDS and XPS characterizations together with RDF analysis, GEN and PUE were adsorbed on the surface of UiO-66 at the same dominant Zr cluster site (O...Zr), while DDZ was bound onto the inferior site via weak hydrogen bonding (H...O), indicating the separation of GEN from PUE was in a competitive manner, while the separation from DDZ was selective. For these three drugs, their adsorption kinetics and adsorption isotherms conformed Pseudo-second-order kinetic model and Langmuir model, respectively, indicating that the monolayer adsorption of isoflavones on UiO-66 surface was the dominant mechanism. The thermodynamic study demonstrated that both adsorptions of GEN and PUE were spontaneous (Δ G 0 < 0), whereas the DDZ adsorption is non-spontaneous (Δ G 0 > 0). Compared to traditional separation techniques, this study provided a simple and efficient approach to isolate structurally similar compounds from natural products in drug discovery. [Display omitted] • UiO-66 can effectively separate GEN from three structurally similar isoflavones(GEN, PUE, and DDZ). • The adsorption of GEN and PUE on UiO-66 was spontaneous, whereas that of DDZ was non-spontaneous. • GEN was separated from PUE and DDZ in a competitive and selective manner, respectively. • MOF adsorption is a promising approach for effectively separating similar structural natural compounds. [ABSTRACT FROM AUTHOR]

In this work, Ru(bpy) 3 2+ encapsulated in metal–organic frameworks (MOFs) UiO-67 (Ru(bpy) 3 2+ /UiO-67) as luminophor was easily prepared and firstly applied in constructing an electrochemiluminescence (ECL) immunosensor to efficiently estimate diethylstilbestrol (DES). The competitive method-based ECL immunosensor platform was fabricated by amino-silicon dioxide which possesses large surface area. The poriness of UiO-67 was splendid so that Ru(bpy) 3 2+ could be easily encapsulated. Ru(bpy) 3 2+ /UiO-67 with excellent ECL luminescence signal existed large specific surface area for easily labeled with antibodies. DES competed with bovine serum albumin-diethylstilbestrol (BSA-DES) for binding to antibody-specific sites in the constructed immunosensor. However DES was micromolecule, which was easier to bond to antibodies than BSA-DES. The ECL signal was gradually decreases with the increase of the concentration of DES. Under optimal conditions, the proposed immunosensor exhibited a wide linear range from 0.01 pg mL −1 to 50 ng mL −1 with a low detetion limit of 3.27 fg mL −1 (S/N = 3). The novel fabricated immunosensor with interference immunity and high stability may cause an attractive approach for the other targets determination. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Li-TFSI was encapsulated in the NH 2 -MIL-101, preventing from attack of water. • The regular oxidation process of doped devices can be performed in an ambient condition. • Amino functionalized Li-TFSI@NH 2 -MIL-101 could inhibit the ion migration of Pb2+. • This approach realizes an enhanced stability for 10-fold that of conventional devices. Lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) is generally regarded as a conventional p-dopant for classical hole transport material Spiro-OMeTAD, which improves the hole mobility and conductivity of hole-transporting layer (HTL). However, the hygroscopic Li-TFSI would absorb moisture and accelerate the degradation of perovskite film, causing a decline in the long-term stability of perovskite solar cells (PSCs). Herein, a novel dopant Li-TFSI endohedral metal–organic frameworks (namely Li-TFSI@NH 2 -MIL-101) is constructed for reducing the amount of Li salt and resisting the attack from water molecules. With a significantly decreased Li salt loading mass, the optimal power conversion efficiency (PCE) of 19.01% is achieved for Li-TFSI@ NH 2 -MIL-101 doped PSCs, which is comparable to that of conventional devices (19.23%). Furthermore, the strong interaction between ammonium groups (–NH 2) and uncoordinated Pb2+ ions would passivate the trap states and inhibit ion migration at perovskite/hole transport layer interface, which further improve the device stability. Importantly, this approach realizes an enhanced stability for approximately 10-fold that of conventional devices at the preliminary stage (time to reduce to 90% of initial PCE). The Li-TFSI@NH 2 -MIL-101 doped PSCs display impressive property stability retaining over 85% of the optimal PCE after 3600 h storage in ambient environment (room temperature and RH ≈ 40%). [ABSTRACT FROM AUTHOR]

Neuron-specific enolase (NSE) is the preferred marker for monitoring small cell lung cancer and neuroblastoma. We devised a dual-signal ratiometric electrochemiluminescence (ECL) sensing strategy for sensitive detection of NSE. In this work, Ru (bpy) 3 2+ functionalized zinc-based metal-organic framework (Ru-MOF-5) nanoflowers (NFs) with plentiful carboxyl groups provide an excellent biocompatible sensing platform for the construction of immunosensor. Importantly, Ru-MOF-5 NFs possess stable and efficient "dual-potential" ECL emission of cathode (−1.5 V) and anode (1.5 V) in the existence of co-reactant K 2 S 2 O 8. Simultaneously, the cathode ECL emitter ZnO-AgNPs are employed as the secondary antibody marker, whose participation amplify the cathode ECL signal as well attenuate the anode ECL emission of Ru-MOF-5 NFs. By monitoring the ECL dual-signal of −1.5 V and 1.5 V and calculating their ratios, a ratiometric strategy of quantified readout proportional is implemented for the proposed immunosensor to precise analyze NSE. Based on optimization conditions, the ECL immunosensor displays the wide linear range of 0.0001 ng/mL to 200 ng/mL and the minimum detection limit is 0.041 pg/mL. The "dual-potential" ratiometric ECL immunosensor effectively reduces system error or background signal by self-calibration from both emissions and improves detection reliability. The dual-signal ratiometric strategy with satisfactory reproducibility and stability provides further development possibilities for other biomolecular detection and analysis. [Display omitted] • The single luminophore Ru-MOF-5 NFs showed "dual-potential" ECL emission. • The "dual-potential" of ECL emission was cathode (−1.5 V) and anode (1.5 V). • ZnO-AgNPs acted as both cathodic luminophore and anodic quencher. • The ratiometric immunosensor provided a novel strategy for NSE detection. [ABSTRACT FROM AUTHOR]

• Highly water-stable and negatively charged UiO-66 TFC membrane was constructed. • The TFC membrane showed high permeability and selectivity for dye and antibiotic. • Antifouling property of UiO-66 TFC membrane presented FRR values higher than 92%. • Size exclusion and electrostatic interaction of UiO-66 TFC membrane were elaborated. Metal-organic frameworks (MOFs) materials show great potential in wastewater separation applications. In this study, zirconium-based MOFs (UiO-66) were prepared and constructed universal, high-performance, and flexible nanofiltration (NF) membrane for various dyes and antibiotics separation. The substrate was constructed by two-steps, a) doping graphene oxide (GO) sheets into the membrane casting solution containing polyacrylonitrile (PAN) and forming 2D-3D connecting pores by phase immersion conversion method (defined as GO@PAN), b) immersing the GO@PAN substrate into dopamine solution to self-polymerize into chain macromolecules, which obtaining good compatible and flexible substrate (defined as PGP). Moreover, the UiO-66 was synthesized via solvothermal method and subsequently coated onto the PGP substrate by vacuum-assisted filtration. Benefiting from the water stability, porous structure, and negative charge of UiO-66, the outstanding filtration performance of the UiO-66/PGP thin-film composite (TFC) membrane was achieved. The pure water permeability of the UiO-66/PGP TFC membrane was 31.33 ± 0.75 L m−2h−1 bar−1, and the rejection rates for dye (Congo red, Methyl orange, Rhodamine B, and Methylene blue) and antibiotic (Tetracycline hydrochloride, Oxytetracycline, and Ciprofloxacin) were above 94%. Therefore, we further explored the retention mechanism of the UiO-66/PGP TFC membrane for dye and antibiotic separation (size exclusion and electrostatic interaction). More importantly, antifouling properties and long-time stability of the UiO-66/PGP TFC membrane were also evaluated. These results indicated that the prepared UiO-66/PGP TFC membrane is promising for wastewater treatment, separation, and purification in many industrial and pharmaceutical fields. [ABSTRACT FROM AUTHOR]