| The fiber optic biosensor plays an important role in the development of life science. As a key technique,the preparation of the opitc sensing material is vital to the fiber optic biosensor with high performance.The biosensitivity can be optimized by the structural adjusting and performance optimizing of the sensing material.Due to their characteristic structure and perporties,the planar ring-conjugated complexes are extensively applied to the sensitive materials.The planar ring-conjugated complex is referred to the complex constructed by the planar ligands with some aromatic rings. Generally,these complexes have stable structures and excellent physical and chemical properties especially luminescence,and have been extensively applied to chemistry,physics,material science,biology,medicine,etc.In order to solve the existing problems in clinical medicine detection and the fiber optic biosensor,in this thesis,the optimized sensing materials are used to the fiber optic biosensors based on fluorescence change.Two biosensors were designed and constructed,and have successfully been used to detect the concentrations of adrenalin (AD)and calf thymus DNA(ctDNA).In this thesis,the systematic studies have been done as following:Firstly, metallophthalocyanines(MPc,M=Mn2+,Fe2+,Co2+,Ni2+,Cu2+)were synthesized and used to catalyze the oxidation of catecholamines(CAs).The influence factors of catalytic efficiency,such as catalytic time and temperature,the pH value of solution and the amount of MPc,have been investigated,and the catalytic mechanism was proposed.Secondly,a novel fiber optic AD biosensor was designed and constructed using FePc as catalyzer.Thirdly,three novel planar ring-conjugated complexes were synthesized and characterized.Interactions of the complexes with ctDNA were explored by UV-Vis spectra,luminescence spectra and viscosity measurements. Fourthly,a fiber optic biosensor for DNA detection based on fluorescence change of [Ru(bipy)2DAFND]2+was fabricated and studied.The main conclusions of this thesis include the following three parts:1.The oxidation of catecholamines catalyzed by MPc(1)MPc were synthesized using dimethylbenzene as solvent.In phosphate buffer solution(PBS),MPc could effectively catalyze three kinds of CAs,namely AD, noradrenalin(NA)and dopamine(DA),to the corresponding oxidation products of adrenochrome,noradrenchrome and melanin.The reaction processes of AD and NA oxidized by MPc were similar,which was different from the oxidation of DA.The catalytic mechanism was proposed,and the order of catalytic efficiency was interpreted based on the electronic structure of the complexes.For the oxidation reaction of AD and NA,the optimal catalytic conditions were determined:pH=8.0,T=55℃,[MPc]=1.00 mg/mL and[AD]/[NA]=5.0×10-4 mol/L.MPc had the catalytic activity order ofηMnPc＞ηFePc＞ηnipc>ηCuPc＞ηCoPcat the optimal catalytic conditions,while MnPc showed worse activity than FePc in low pH environment,indicating that FePc could be used in larger pH range. cAs for the oxidation of DA,the product was melanin,which is different from the oxidation of AD and NA.The optimal conditions are pH 8.0,[MPc]=1.00 mg/mL [DA]=5.6×10-4mol/L,the temperatures are different for different MPc.At 55℃,the order of catalytic efficiency isηMnPc>ηFePc＞ηCoPc≈ηCuPc＞ηfNiPc.(2)A novel fiber optic AD biosensor based on the oxidation of AD by O2 was designed and fabricated using FePc as catalyzer.The performance of the biosensor was investigated.The dissolved oxygen and AD content were evaluated by relative phase delay△(?).In PBS with pH 7.4,a linear relationship between△(?)and AD concentration was observed in the range of 2.0×10-6～9.0×10-5mol/L,and the detection limit is 4.0×10-7mol/L.The biosensor has good stability and repeatability, and its response time is 10 min.2.DNA-binding properties of two complexes containing organosulfonate ligand (1)Two novel organosulfonate complexes,[M(phen)2(ans)2]·H2O(M=Cd 1,M= Pb 2),were obtained from the reaction of 1,10-phenanthroline(phen),sodium 4-aminonaphthalene-1-sulfonate(Naans)and Cd(OAc)2·2H2O or Pb(NO3)2 in a mixed solvent of water and methanol at room temperature.The compounds were characterized by elemental analysis,IR,and single crystal X-ray diffraction method. In spite of the different cell systems,the asymmetric units of the complexes were identical,namely one neutral compound and one water molecule.The coordination geometries of the central atom were the same within two complexes,showing a distorted octahedral environment with MN4O2.(2)Interactions of the complexes with ctDNA were studied by UV/Vis spectra, luminescence titrations,steady-state emission quenching by[Fe(CN)6]4-,DNA competitive binding with ethidium bromide(EB)and viscosity measurements.The results indicated that there were two interactions between the complexes and DNA, namely the electrostatic interaction and intercalation,with the binding constants of 1.82×l05 L/mol for 1 and 4.96×104 L/mol for 2 in buffer of 50 mmol/L NaCl and 5 mmol/L Tris-HCl(pH 7.1,Tris buffer).3.DNA-binding properties of the polypyridyl Ru(Ⅱ)complex(1)A new Schiff base of 4,5-diazafluorene-9-p-nitrophenylhydrazone(DAFND) was synthesized using 1,10-phenanthroline and p-nitrophenylhydrazine as raw materials.DAFND and 2,2'-bipyridyl(bipy)acting as the main and auxiliary ligands, a polypyridyl complex of[Ru(bipy)2DAFND](ClO4)2 was obtained.The synthesized compounds were characterized by IR,1H NMR,elemental analysis,ES-MS and single crystal X-ray diffraction method.(2)Interaction of the complex with ctDNA was explored by UV/Vis absorption spectra,luminescence spectra and viscosity measurements,illustrating that the complex interacted with ctDNA via intercalation,with the binding constant of 8.91×105 L/mol in Tris buffer.(3)A fiber optic biosensor for DNA detection based on fluorescence change was fabricated,using[Ru(bipy)2DAFND]2+embedded in CA as indicator for the optic sensing membrane.The performance of the biosensor was studied and it has the analytical range of 3.6×10-7～1.56×10-6mol/L,response time of 70 s and detection limit of 8.4xl0-8mol/L in Tris buffer(pH 7.1).The biosensor showed excellent reproducibility and stability and its working temperature was below 40℃.
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