Synthesis Of Coordination Polymers Based On Polycarboxylic Acid And Study Of Antibacterial Activity Of Silver-based Coordination Polymers

Recently,much interest has been focused on the design and synthesis of coordination polymers,for their various intersting architectures and potential application.People have synthesized a lot of coordination polymers with novel structure by using carboxylic acid ligands.Coordination polymers have been widely applied to antibacterial fields such as ceramics,surgical devices and cosmetics that attributes to their long-range reliability and high safety.In this dissertation,the carboxylates were chosen as main building block,and successfully construct eight coordination polymers.Study focused on the fact that the structures and antibacterial activities have been analyzed for silver-based coordination polymers.The contents and main points in this paper were summarized as follows:(1)A series of Cd(II),Ni(II)and Ce(III)coordination polymers have been synthesized under hydrothermal conditions using 3-(3-carboxy-phenoxy)phthalic acid(H3cppa)organic ligands,namely[Cd(Hcppa)(H2O)2(CH3OH)]n(1),[Ni3(cppa)2(bipy)4]n·6nH20(2),[Ce(cppa)(phen)]n(3).1 forms a 3D supramolecular structure linked by intermolecular hydrogen bonds based on 1D chains.2 structure analysis indicated that it was a 3D porous framework.3 shaped configurations of rectangle and parallelogram shaped 1D channel in structures.Additionally,1-3 had the good thermal stability property and characterized by X-ray single crystal diffraction,FTIR,PXRD,TGA and fluorescence.(2)Silver nitrate react with 2-(4-carboxyl phenoxy)terephthalic acid(H3cia)and aspartic acid,and result five coordination polymers,namely[Ag(H2cia)(bpa)]n·2nH20(4),[Ag2(cia)(bpp)2·H20]n·4nH20(5),[Ag3(D-asp)2(N03)]n·nH20(6),[Ag3(L-asp)2(N03)]n·nH20(7)and[(D-asp)(L-asp)(N03)2]n·2nH20(8).4 and 5 were synthesized constituted silver nitrate and H3cia,forms a 2D wireless network structure by diffusion method.6-8 were obtained by the reaction of AgN03 and aspartic acid,and stirring at room temperature.The 3D framework of the 6 and 7 consists of six-helix bundle with a helical pitch of 70.6 A.A 2D coordination polymer sheet was made up of D/L-aspartic acid chains alternate in the 8.Additionally,4-8 had the good thermal stability property and photostability,characterized by X-ray single crystal diffraction,fluorescence,FTIR,PXRD and TGA.(3)The antibacterial activities of Ag-based coordination polymers(4-8)were investigated against Gram-negative bacteria(E.coli,P.aeruginosa)and Gram-positive bacteria(S.aureus)by determining the minimal inhibitory concentration(MIC)benchmark,the growth inhibition assay of bacteria and using an inhibition zone testing.The study showed that the antibacterial activity of 8 was the best,and MIC could reach 5-10 ppm.In addition,the mechanism of antibacterial activity of Ag-based coordination polymers were also taken into account by using TEM,fluorescent microscopy,solid ultraviolet visible diffuse reflectance spectroscopy and inductively coupled plasma atomic emission spectrometry(ICP-AES).