Synthese, structure of three Zn-MOFs and potential sensor material for tetracycline antibiotic in water: {[Zn(bdc)(4,4′-bidpe)] •H2O}n

Recently, enough attention has been paid to the pollution and damage of antibiotics in water. Zn-metal organic frameworks (Zn-MOFs), as a novel kind of sensing material, have been tentatively developed a highly effective candidate to detect antibiotics in water. A series of Zn-MOFs material named {[Zn (bdc)(4,4'-bidpe)]center dot H2O](n). (1), {[Zn-3 (bdc)(2) (tib)(2)(HCOO)(2)]center dot 4(H2O)-0.5(CH2Cl2)}(n) (2), [Zn (bdc)(bidpa)](n) (3) were successfully constructed under the condition of solvothermal, using 4,4'-bis(imidazolyl)diphenyl ether (4,4'-bidpe), 1,3,5-firs (1-imidazolyl)benzene (fib), 4,4'-bis(imidazolyl)diphenyl amino (4,4'-bidpa) and 1,4-benzenedicarboxylate (H(2)bdc). Three complexes were characterized by X-ray single-crystal diffraction, elemental analysis, IR spectra and thermogravimetric (TG) analysis. Complex 1 has a three-dimensional (3D) framework that crystallizes in the triclinic system, Pi space group. Complex 2 crystallizes in the monoclinic system, C2/c space group featuring a 3-nodal (3,3,4)-connected network with point symbol of 2{8(3)}2{8(6)}{8.10(2)}. Complex 3 belongs to the tetragonal system, I4(1)/acd space group with two-fold interpenetrating architecture. A linear pH sensing of complex 1 (I = 1035.2 pH + 726.9) between the fluorescence intensity and pH values was achieved through the fluorescence quenching experiment in the acidic condition. The fluorescence quenching experimental results showed that complex 1 exhibits sensitive response to TC with detection limit of 3.72 x 10(-7 )M based on its effective spectral overlap and adsorption preconcentration with tetracycline (TC).