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Triazole polycarboxylic acid ligands are widely employed in the construction of MOFs due to their strong coordination ability and flexible coordination modes. In this work, three novel complexes (Pb(MCTCA)(H2O) (1), Co(HMCTCA)2(H2O)2 (2) and Cu(HMCTCA)2(H2O)2 (3)) based on the H2MCTCA ligand (5-methyl-1-(4-carboxyl)-1H-1,2,3-triazole-4-carboxylic acid) were successfully synthesized under hydrothermal conditions, respectively. X-ray single crystal structure analysis shows that complex 1 is a 3D network structure, where the central metal Pb(II) is six coordinated to form deformed triangular prism geometry. The complexes 2 and 3 are both 2D layer supramolecular structures connected through intermolecular hydrogen, where the central metals (Co/Cu) are six coordinated to form octahedral configuration geometry. Based on functional properties, it is found that complex 1 exhibits excellent detection ability for small-molecule drugs (azithromycin, colchicine and balsalazide disodium) and actinide cations (Th4+ and UO22+) within a lower concentration range without interference from other components. In particular, the detection limits of three small-molecule drugs are all lower than 0.30 μM. In addition, complexes 2 and 3 exhibited excellent catalytic reduction performance toward p-nitrophenol (PNP), with a reduction efficiency exceeding 98%. These experimental results evidence that complexes 1–3 have potential application prospects in fluorescence sensing and catalytic reduction. [ABSTRACT FROM AUTHOR]

Three MM-MOFs based on the reaction of H 6 TTHA ligand, Ln(NO 3) 3 ·6H 2 O (Ln=Eu, Sm, Dy) and Zn(NO 3) 2 ·6H 2 O under hydrothermal conditions. Complex 1 had the fluorescence sensing abilities for metal ions, anions, and organic nitro compounds. It was worth noting that complex 1 showed prominent sensitivity for TNP, the detection limit was as low as 1.14 μM. [Display omitted] Metal-organic frameworks composed of two metals in the structure are called mixed-metal metal organic frameworks (MM-MOFs). In this work, we constructed three MM-MOFs, namely [Zn 3 Eu 2 (TTHA) 2 (H 2 O) 6 ]·6H 2 O (1), [Zn 3 Sm 2 (TTHA) 2 (H 2 O) 6 ]·2H 2 O (2) and [ZnDy(HTTHA)(H 2 O) 4 ]·2H 2 O (3) by the reaction of H 6 TTHA ligand (H 6 TTHA = 1, 3, 5-triazine-2, 4, 6-triamine hexaacetic acid), Ln(NO 3) 3 ·6H 2 O (Ln = Eu, Sm, Dy) and Zn(NO 3) 2 ·6H 2 O under hydrothermal conditions. The complexes 1 – 2 were a 3D microporous structure and complex 3 formed a 3D network structure. Furthermore, complex 1 exhibited excellent fluorescence properties. We explored the fluorescence sensing abilities of complex 1 for metal ions, anions, and organic nitro compounds. The experimental results showed that complex 1 could sensitively and efficiently detect Fe3+, Cr 2 O 7 2- ions and 2,4,6-trinitrophenol (TNP). It was worth noting that complex 1 showed prominent sensitivity for TNP, the detection limit was as low as 1.14 μM. [ABSTRACT FROM AUTHOR]

A novel naphthalene based fluorescence probe NBDH was designed and synthesized. Probe NBDH exhibited highly selective and sensitive responses towards Al3+ in HEPES-NaOH buffer solution (pH = 7.4). In addition, the detection of NBDH to Al3+ could be achieved through dual channels embodied in significant fluorescent turn-on signal and ratiometric absorbance response. The stoichiometry ratio of NBDH-Al3+ was 1:1 by fluorescence job' plot and binging mechanism was further varified by the FT-IR, NMR titration and HRMS. Furthermore, NBDH was achieved in real sample detection, and a series of color test paper were developed for visual detecting Al3+ ions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Z with benzothiazole fluorophore was synthesized and characterized. • Z exhibits a 9-fold fluorescence enhancement and ratiometric absorption for Al3+. • LOD for Al3+ was determined by fluorescence and absorbance-ratiometric detection. • Z was applied to form paper strip sensor for Al3+ and cell imaging in HSC. Abstract Chemosensor Z including benzothiazole fluorophore was synthesized and characterized with NMR and HRMS spectroscopic techniques. Z exhibited fluorescence turn-on and ratiometric absorbance detection of Al3+ ions based on the combination mechanism of CHEF and ESIPT processes. Moreover, the stiochiometry between Z and Al3+ were determined 2:1 through job's plot and HRMS, and the limit of detection was determined as 8.47 nM which was qualified in the detection of Al3+ in drinking water. Especially, Z was achieved in fast identification the existence of Al3+ by filter paper, and cell imaging in human stromal cell (HSC). [ABSTRACT FROM AUTHOR]

Abstract A new naphthalene-quinoline based chemosensor L was prepared and structurally characterized. L exhibited excellent selectivity and sensitivity to Al3+ through distinct fluorescence enhancement (335-fold) and ratiometric detection in DMF/H 2 O (v/v, 1/9) based on the combined mechanisms of ESIPT and CHEF. The recognizing behavior of L toward Al3+ had been investigated in detail through Job's Plot, FT-IR, HNMR, and HRMS analysis. The limit of detection (LOD) for Al3+ was as low as and 3.67 × 10−8 M. L was successfully applied in real sample detection and construction of molecular logic gate. Moreover, L was verified to be of low cytotoxicity and good imaging characteristics for the detection of Al3+ in cells HSC. Graphical abstract Unlabelled Image Highlights • A naphthalene-quinoline based chemosensor L was prepared and structurally characterized. • L exhibited excellent selectivity and sensitivity to Al3+ through fluorescence enhancement (335-fold) and ratiometric detection. • The limit of detection (LOD) for Al3+ was determined as 3.67 × 10−8 M. • L was successfully applied in the detection of Al3+ in cells HSC. [ABSTRACT FROM AUTHOR]

A novel naphthalimide-based colorimetric and fluorescent turn-on chemosensor for Al3+ was synthesized and characterized with spectroscopic techniques. In MeOH solution, BPAM showed high selectivity and sensitivity to Al3+ by a 60-fold fluorescence enhancement and blue-shift absorption with visible color changes attributed to the contribution of chelation enhanced fluorescence (CHEF) and inhibition of intramolecular charge transfer (ICT). A 1:1 BPAM-Al3+ complex confirmed by job’s plot and HRMS with a binding constant of 6.37 × 104 M− 1, and the detection limit for Al3+ was as low as 1.59 × 10− 7 M. BPAM was successfully applied in real sample detection and assessing the existence of Al3+ by a colorimetric method on filter paper. Furthermore, the fluorescent signals of BPAM were designed to construct an INHIBIT molecular logic gate. [ABSTRACT FROM AUTHOR]

A new schiff-base receptor L based on naphthalimide had been investigated as a selective and sensitive chemosensor for Al 3+ in CH 3 OH. Upon addition of Al 3+ , L showed a 39-fold enhancement at 508 nm with colorimetric and fluorometric dual-signaling response which might be induced by the integration of ICT and CHEF. A 1:1 stoichiometry for the L -Al 3+ complex was formed with an association constant of 1.62×10 4 M −1 , and the limit of detection for Al 3+ was determined as 7.4 nM. In addition, the potential utility of L in sensing Al 3+ was also examined in real water samples. [ABSTRACT FROM AUTHOR]

A dual-function probe BHMH was synthesized and characterized functioned with benzothiazole as signal unit for the simultaneous detection of Zn2+ and Al3+ DMF/H 2 O (1/1, v/v, 0.01 M HEPES, pH = 6.0). Probe BHMH achieved in the recognition of Zn2+ and Al3+ both through obvious fluorescence turn-on and absorbance ratiometric response. The limit of detection (LOD) according to the titration of fluorescence for Zn2+ and Al3+ were 1.27 × 10−7 M and 1.42 × 10−7 M, respectively. Furthermore, the significant color changes could be detected by naked eye whatever under ultraviolet-lamp or daylight. According to Job plot, the binding ratio of BHMH with Zn2+ and Al3+ were determined as 1:1 and 2:1, respectively. The binging detail was further confirmed by 1H NMR titration and ESI-MS analysis as well. Moreover, probe BHMH was successfully applied in the detection Zn2+ and Al3+ in real sample and test stripe. Unlabelled Image • Chemosensor BHMH with benzothiazole fluorophore was synthesized and characterized. • BHMH exhibits highly selective to Zn2+ and Al3+ with significant fluorescence turn-on and color change. • Limit of detection (LOD) for Zn2+ and Al3+ were all reached the level of 10−8 M. • BHMH was successfully applied in the detection of Zn2+ and Al3+ in test paper. [ABSTRACT FROM AUTHOR]