Synthesis, DNA Binding Spectrscopy And Bio-toxicity On Zebrafish Embryo Studies Of Cu (Ⅱ)/Zn (Ⅱ)-life Ligand Complexes

The research of Cu(Ⅱ)/Zn(Ⅱ)-life ligand complexes is one of the most active areas in transition metal complexes scientific research.The biological activities of these complexes play an important part in lives'research. Its medical effect is concerned of the important aspects. In this paper, new Cu(Ⅱ)/Zn(Ⅱ)-life ligand complexes are synthesized, a series of known complexes were chosen to study as comparison reference. A variety of methods are used to research the biological activities:The interaction of the complexe with sperm DNA was investigated by electric absorption spectrscopy,ethidium bromide(EB) fluorescence spectrscopy and gel electrophoresis measurements.The bio-toxicity of the complexe was determined by zebrafish embryos. With the expection of providing theoretical basis for drug development of new metal complexes. Main research results are as follows:(1) A novel complex of [Zn(Trp)(phen)2]Cl·7H2O (1) (Tip=L-Tryptophan, phen=Phenanthroline) was synthesized and characterized by elemental analysis, IR spectrscopy and TG-DTA.(2) [Zn(Trp)(phen)2] Cl·7H2O is studied compared with two known complexes [Zn(phen)2] Cl2·5H2O(2) and [Zn(phen)Cl2](3) The results of electronic absorption spectrometry and fluorescence spectrometry indicated that the three Zn(Ⅱ)-life ligand complexes bond to DNA by different modes,with the order of the binding ability of the complexes to DNA:complex 1> complex 2> complex 3. The results of agarose gel electrophoresis experiment indicated that after 10 min of the action between complexes and pBR322 DNA in the presence of vitamin C as a reducing regent,complex 1 has significant effect on pBR322 DNA, but complex 2 and complex 3 have no obvious effect on pBR322 DNA.According to time,the activity of complex 1 cleaving pBR322 DNA is stronger. Concerning the concentration, when the concentration of complex is 2.5μmol·L-1,nearly a half of pBR322 DNA is cleaved from typeⅠinto typeⅡwith complex 2,while there is only typeⅠwith complex 3. When the concentration of complex is 10μmol·L-1,pBR322 DNA is completely cleaved from typeⅠinto typeⅡwith complex 2,what is more,some typeⅢappears, while there is no typeⅢappears with complex 3 although pBR322 DNA is also completely cleaved from typeⅠinto typeⅡ. The results indicated that complexes 2 cutting activity is stronger than complexes 3. To sum up,the three complexes cleave pBR322 DNA in the presence of vitamin C as a reducing regent with the order of cleavage activity of the complexes to DNA:complex 1> complex 2> complex 3. The bio-toxicity of the complexes on zebrafish embryos is studied by studying the mortality of 24hpf,median lethal dose and hatching rate of 72hpf of zebrafish embryos. The results indicated that the bio-toxicity of the Zn(Ⅱ)-life ligand complexes on zebrafish embryos is increased in the order:complex 3 complex 5. The results of agarose gel electrophoresis experiment indicated that after 10 min of the action between complexes and pBR322 DNA in the presence of vitamin C as a reducing regent,complex 4 has significant effect on pBR322 DNA,but complex 5 have no obvious effect on pBR322 DNA.According to time,the activity of complex 4 cleaving pBR322 DNA is stronger than complex 5. The bio-toxicity of the complexes on zebrafish embryos is studied by studying the mortality of 24hpf,median lethal dose and hatching rate of 72hpf of zebrafish embryos. The results indicated that the bio-toxicity of the Cu(Ⅱ)-life ligand complexes on zebrafish embryos is increased in the order:complex 4< complex 5. It can be said that the 1,10-phenanthroline increases the bio-toxicity of complex 4. To sum up,the novel zinc complex:[Zn(Trp)(phen)2] Cl·7H2O is more suitable to be studied as candidates of highly effective and low poisonous drugs.