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A photoresponsive hollow molecularly imprinted polymer (PHMIP) was fabricated for photoresponsive recognition and determination of trace bisphenol A (BPA) in aqueous media using a water-soluble azo compound as the functional monomer. The PHMIP was prepared on sacrificial silica microspheres by surface imprinting and subsequent removal of the silica core. The PHMIP displayed photocontrolled recognition for BPA. SEM, TEM, FT-IR, TGA and N 2 adsorption-desorption analyses confirmed successful formation of the hollow structure. The PHMIP displayed higher binding capacity, a larger specific area, and faster mass transfer rate than its corresponding surface molecularly imprinted polymer. The PHMIP was used to determine trace BPA in real samples with a limit of detection of 0.5 ppm. For samples spiked at 0–10 ppm, the BPA recoveries were in the range of 93.0%–99.0%. This PHMIP-based method provides convenient and inexpensive detection method for trace BPA in environmental samples. This method is especially suitable for determining materials that do not possess specific spectroscopic or luminescent properties. [ABSTRACT FROM AUTHOR]

In acidic solution, a serials of water-soluble coordination polymers (CPs) were isolated as zonal 1D-CPs 1,3-propanediaminetetraacetato lanthanides [ Ln (1,3-H 3 pdta)(H 2 O) 5 ] n ·2Cl n ·3 n H 2 O [ Ln =La, 1 ; Ce, 2 ; Pr, 3 ; Nd, 4 ; Sm, 5 ] (1,3-H 4 pdta=1,3-propanediaminetetraacetic acid, C 11 H 18 N 2 O 8 ) in high yields. When 1 eq. mol potassium hydroxide was added to the solutions of 1D-CPs, respectively, two 1D-CPs [Ln(1,3-H 2 pdta)(H 2 O) 3 ] n ·Cl n ·2 n H 2 O [ Ln =Sm, 6 ; Gd, 7 ] were isolated at room temperature and seven 2D-CPs [ Ln (1,3-H 2 pdta)(H 2 O) 2 ] n ·Cl n ·2 n H 2 O [ Ln =La, 8 ; Ce, 9 ; Pr, 10 ; Nd, 11 ; Sm, 12 ; Eu, 13 ; Gd, 14 ] were isolated at 70 °C. When the crystals of 1–4 were hydrothermally heated at 180 °C with 1–2 eq. mol potassium hydroxide, four 3D-CPs [ Ln (1,3-Hpdta)] n · n H 2 O [ Ln =La, 15 ; Ce, 16 ; Pr, 17 ; Nd, 18 ] were obtained. The two 2D-CPs [ Ln (1,3-Hpdta)(H 2 O)] n ·4 n H 2 O (Sm, 19 ; Eu, 20 ) were isolated in similar reaction conditions. With the increments of pH value in the solution and reaction temperature, the structure becomes more complicated. 1–5 are soluble in water and 1 was traced by solution 13 C{ 1 H} NMR technique, the water-soluble lanthanides 1 and 5 show catalytic activity to ester hydrolysis reaction respectively, which indicate their important roles in the hydrolytic reaction. The europium complexes 13 and 20 show visible fluorescence at an excitation of 394 nm. The structure diversity is mainly caused by the variation of coordinated ligand in different pH values and lanthanide contraction effect. Acidic conditions are favorable for the isolations of lanthanide complexes in different structures and this may helpful to separate different lanthanides. The thermal stability investigations reveal that acidic condition is favorable to obtain the oxides at a lower temperature. [ABSTRACT FROM AUTHOR]

A water-stable metal-organic framework (MOF) EuNDC has been synthesized for selective detection of the well-known contaminant and toxicant picric acid (PA) in aqueous solution. Due to the photo-induced electron transfer and self-absorption mechanism, EuNDC displayed rapid, selective and sensitive detection of PA with a detection limit of 37.6 ppb. Recyclability experiments revealed that EuNDC retains its initial luminescent intensity and same quenching efficiency in each cycle, suggesting high photostability and reusability for long-term sensing applications. The excellent detection performance of EuNDC makes it a promising PA sensing material for practical applications. [ABSTRACT FROM AUTHOR]

A near infrared luminescent MOFs thermometer (Nd 0.676 Yb 0.324 BTC) was prepared via a simple solvothermal method using Ln 3+ (Ln=Nd, Yb) ions and 1, 3, 5-benznenetricarboxylic acid (H 3 BTC), and characterized by PXRD, TGA, ICP, and photoluminescence (PL) spectrum. These results indicate that the Nd 0.676 Yb 0.324 BTC displays high relative sensitivity and excellent repeatability in the physiological temperature range (288–323 K), and the maximum relative sensitivity is determined to be 1.187% K −1 at 323 K. These NIR luminescent MOFs may have potential applications in physiological temperature sensing. [ABSTRACT FROM AUTHOR]

Design and synthesis of a series of isostructural lanthanide metal-organic frameworks (LnMOFs) serving as phosphors by coordinate the H 2 TIPA (5-(1 H -tetrazol-5-yl)isophthalic acid) ligands and lanthanide ions is reported. The color of the luminescence can be tuned by adjusting the relative concentration of the lanthanide ions in the host framework GdTIPA , and near-pure-white light emission can be achieved. [ABSTRACT FROM AUTHOR]

Abstract: Three metal–organic complexes Cd(HBIDC)(phen)2·4H2O (1), [Cd(BIC)(phen)] n (2) and {[Eu(HBIDC)(H2BIDC)(H2O)]·H2O} n (3) (H3BIDC=benzimidazole-5,6-dicarboxylic acid, H2BIC=benzimidazole-6-carboxylic acid, phen=1,10-phenanthroline) have been synthesized under hydro(solvo)thermal conditions and structurally characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. With similar reaction conditions, reactions of the same ligand with different metal cations selected from different blocks (d-block and f-block) result in different coordination modes of carboxylate groups and final frameworks of complexes 1 and 3. The decarboxylation was observed in complex 2 and resulted in the formation of BIC2− ligand. Complexes 1–3 have intense fluorescent emissions at room temperature in dimethylsulfoxide (DMSO) solution and in the solid-state, which indicate they are potential fluorescence materials. The quantum yields and fluorescence lifetimes of these three complexes were systematically studied. [Copyright &y& Elsevier]