Synthesis And Antimicrobial Properties Of Organic Coordination Polymers With Transition Metals

Transition metal organic complexes,as a kind of very important crystal materials,have a promising application in many fields,such as sensing,ion recognition,drug release and solid antimicrobial.In this paper,on the premise of improving the thermal stability of the complexes and making it have good antibacterial properties,three kinds of transition metal organic complex crystal materials with novel structures were synthesized by traditional solvothermal synthesis method.By means of elemental analysis,infrared spectroscopy and single crystal/powder-XRD,the crystal structures of the three kinds of crystal materials were analyzed.In addition,the thermal stability and antimicrobial properties of these three crystalline materials were studied.By selecting appropriate transition metals and nitrogen-containing compounds to construct complexes,not only the stability of the compounds themselves can be improved,but also the properties of the complexes have both organic compounds and inorganic metals,thus enriching the application of the crystal materials of the complexes in many fields.The detailed research in this paper is as follows:A new complex[Ni₂(en)₄Cl₂]Cl₂(1)was successfully synthesized by solvothermal method using transition metal Ni²⁺ion as metal center ion and ethylenediamine(en)as organic ligand.Complex 1 has a zero-dimensional(0D)structure,and forms a three-dimensional supramolecular network structure through N-H...Cl hydrogen bond by single crystal X-ray diffraction analysis.The thermal stability of complex 1 was tested.The results showed that the crystal skeleton material of complex 1 began to collapse at about 230?,and there was only one weight loss phenomenon,which also indicated that the thermal stability of complex 1 was significantly improved after coordination with transition metal.In addition,the antibacterial properties of complex 1 were also studied by the bacteriostatic zone method and the growth curve method.The results showed that complex 1 exhibited better antibacterial properties against Gram-negative bacteria compared with Gelan-positive bacteria.Therefore,complex 1 has potential application prospects in the aspects of thermal stability and antibacterial properties.A new complex[Zn(en)Cl₂]_n(2)with a one-dimensional(1D)chain structure was successfully synthesized by solsolothermal method using transition metal Zn²⁺ion as the metal center ion and ethylenediamine(en)as the organic ligand,and a three-dimensional supramolecular network structure was formed by N-H...Cl hydrogen bonding.The thermal stability of complex 2 was tested.The results showed that the crystal skeleton material of complex 2 began to collapse at about 160?,and there was only one weightlessness phenomenon,which also indicated that the thermal stability of complex 2 was significantly improved after coordination with transition metal.In addition,the antibacterial properties of complex 2 were tested.The results showed that complex 2 showed better antimicrobial properties against Gram-positive bacteria compared with Gelam-negative bacteria,and the antimicrobial effect was significantly better than complex 1.Therefore,complex 2 also has potential application prospects in thermal stability and antibacterial properties.Complex[Zn(L^2-)(H₂O)₄](3)was successfully synthesized by solvothermal synthesis by H₂L(H₂L=4-[(8-hydroxy-5-quinolinyl)azo]-benzenesulfonic acid)and Zn(II)ion.Complex 3 exhibits a zero-dimensional(0D)structure,which is connected into three-dimensional(3D)supramolecular network by hydrogen bonding and?-?stacking interaction.The thermal stability of complex 3 was tested.The results showed that the crystal skeleton material of complex 3 began to collapse at about130?,and there was only two weightlessness phenomenon,which also indicated that the thermal stability of complex 3 was significantly improved after coordination with transition metal.In addition,the antibacterial properties of complex 3 were tested.The antibacterial properties of complex 3 in gram negative bacteria were better than that of gram positive bacteria by comparing the antibacterial activities,which may be provided a certain reference for the antibacterial research of metal organic coordination polymer.