Electrochemical Polymerization Of Fused Ring Compounds With Carboxyl Group And Its Application In Uric Acid Detection

The chain of the conducting polymer usually is a rigid molecular structure, and thereforeis insoluble. Although the electrochemical polymerization method has many advantages, thereare still many difficulties of preparing conducting polymer film with favorable solubility. Theresearch of preparing conducting polymer film with favorable solubility is still very necessaryand significant. In order to improve the solubility of conducting polymers, polar group isincorporated into the polymer backbone. Carboxyl functional groups can not only increase thesolubility of conducting polymer, but also can be used to prepare the electrochemical biosensor.In this dissertation, poly（N-（9-fluorenylmethoxycarbony）-glycine）, poly（3-thienylacetic acid）and poly（3-thiophenemalonic acid） were prepared by electrochemical polymerizationsuccessfully. In addition, a molecularly imprinted electrochemical sensor based onpoly（3,4-ethylenedioxythiophene-co-3-acetic acid thiophene） film was prepared.1. Poly（N-（9-fluorenylmethoxycarbony）-glycine） film was prepared in boron trifluoridediethyl etherate （BFEE） by electrochemical polymerization for the first time. The electricalconductivity of poly（N-（9-fluorenylmethoxycarbony）-glycine） film was0.49S cm^-1. The onsetoxidation potential of N-（9-fluorenylmethoxycarbony）-glycine in pure BFEE was0.60V vs. Pt.FT-IR and1H NMR spectral investigations indicated that electrochemical polymerization ofN-（9-fluorenylmethoxycarbony）-glycine mainly occurred at C2,C7positions. Fluorescentspectral studies indicated that poly（N-（9-fluorenylmethoxycarbony）-glycine） was a goodblue-light emitter.2. Poly（3-thienylacetic acid） film was prepared in BFEE containing25％trifluoroaceticacid （by volume） by electrochemical polymerization for the first time.3-thienylacetic acid hada lower oxidation potential （0.38V vs. Pt） in this medium. As-formed polymer had goodelectrochemical activities．The conductivity of film was7S cm^-1and was soluble in water,methanol and alcohol. Fluorescent spectral studies indicated that poly（3-thienylacetic acid）was a good blue-light emitter.3. Poly（3-thiophenemalonic acid） film with conductivity of16S cm^-1was synthesizedelectrochemically by direct oxidation of3-thiophenemalonic acid in BFEE containing50％trifluoroacetic acid （by volume） for the first time. Poly（3-thiophenemalonic acid） filmobtained from this medium showed good electrochemical behavior and stability. Thermalanalysis indicated that the film had the better thermal stability. FT-IR spectra and1H NMRspectra confirmed that the polymer chains grew mainly via the coupling of the monomer at C2,C5positions. The fluorescence spectra suggested that soluble poly（3-thiophenemalonicacid） was a good blue-light emitter in water.4. A new kind of conducting copolymer,poly（3,4-ethylenedioxythiophene-co-3-thienylacetic acid）, was deposited on Pt electrode withuric acid which was the template to form a molecularly imprinted polymer for theamperometric detection of uric acid. A good linear relationship between current and uric acidconcentration from0.15to1.35mmol was obtained. The sensitivity of the preparedmolecularly imprinted polymer electrode was calculated to be25.11μA mmol^-1cm^-2. Thelimit of detection for this molecularly imprinted polymer was found to be0.04mmol at asignal-to-noise ratio of3. In addition, regeneration and reproducibility of this sensor were alsoinvestigated and the experimental results indicated that the sensor had good regeneration andreproducibility.