| In recent years, with the development of economy, people’s living standards is improving constantly. Environmental protection, food sanitation and medicine safety have received more attention from people. Therefore, it is important to establish a convenient, sensitive, economical and practical method which is used to detect food,pharmaceutical and pollutant. Electrochemical analysis method is simple, convenient operation, easy automation and miniaturization in the detection of material. So it is wide application and development in material analysis. In order to prepare a good selectivity,high stability and sensitivity modified electrode, it is extremely important to screen appropriate modification material and preparation method. Acetylene black which is an amorphous carbon nano-material and lower price, good electrical conductivity, high stability, large surface area, can be used as modify material. Moreover, due to Many different types of monomer and polymer, polymer film not only possess different structure but can form uniformity film. It is used widely in the field of medicine, Life and Environmental Sciences. Therefore, choosing acetylene black and different type polymer film as modify material, the paper prepared four different modified electrodes to detect vanillin, paracetamol, Chloramphenicol and naphthol isomers. the main contents are as follows:1. a new modified electrode（AB/PABSA/GCE） was prepared by acetylene black and amino benzene sulfonic acid and it was characterized by electrochemical impedance spectroscopy（EIS）. Study the influence of experimental conditions, such as type of buffer solution, p H, scan rate, etal. The results indicated that the catalytic effect of AB/PABSA/GCE is best and the electrode process is irreversible and controlled by absorption. Some important kinetics parameters of electrochemical process were calculated. In the range of 5.0 ×10-6 mol/L 4.6 ×10-4 mol/L, a good linearity relationship between oxidation peak current and concentration of Van was observed by chronoamperometry. The detection limit is 2.09 ×10-7 mol/L. the recovery is in range of 93.0 % 114.2 %. The mothed was applied to detect chocolate sample2. Poly L-Histidine/Acetylene Black modified electrode（Poly-（L-His）/AB/GCE）was prepared by drop coating and electroploymerization and was characterized by EIS.The electrochemical behavior of parscetamol（PCT） on Poly-（L-His）/AB/GCE were investigation by cyclic voltammetry（CV）. The results indicated that electrochemical response of PCT on Poly-（L-His）/AB/GCE is much greater than GCE electrode, andpeak current increases by a factor of 2.1 times. the electrode process is reversible and controlled by absorption. Some important kinetics parameters of electrochemical process were calculated. In the range of 8.0×10-7 1.0×10-4 mol/L, a good linearity relationship between peak current and concentration of PCT was determined by differential pulse voltammetry（DPV）. The detection limit is 7.72×10-8 mol/L. The mothed was applied in the determination of PCT in Ganmaoling granules sample, and the recovery is between 97.8% and 105.2%.3. A new modified electrode（p-PTA/CS-AB/GCE） was fabricated by Chitosan,Acetylene Black and Phospho-tungstic Acid. The modified electrode was characterized by scanning electron microscope（SEM） and EIS. Study the electrochemical behavior of chloramphenicol（CAP） on p-PTA/CS-AB/GCE by CV. The results show that the electrochemical response of CAP is more obvious on p-PTA/CS-AB/GCE. the electrode process is reversible and controlled by absorption. Some important kinetics parameters of electrochemical process were calculated. In the range of 5.0×10-7 mol/L 1.0×10-4mol/L, a good linearity relationship between reduction peak current and concentration of CAP was observed by DPV. The detection limit is 5.13×10-8 mol/L. The mothed was applied in the determination of CAP in chloramphenicol tablets sample, and the relative standard deviation is 1.4 %. The recovery is between 97.8% and 105.2%.4. According to the references, nano Cupric oxide was synthesized and it was used to prepare poly L-tyrosine/copper oxide-acetylene black modified electrode（Poly-（L-Tyr）/Cu O-AB/GCE）. Survey the micro-morphology of nano-Cu O and Cu O-AB by scanning electron microscope. The experimental conditions of p H, type of buffer solution, modifier dosage and scan rate were optimized and the electrochemical behavior of naphthol isomers was study by CV. The results show that the electrode process of naphthol isomers on Poly-（L-Tyr）/Cu O-AB/GCE are irreversible and controlled by absorption. Diffusion coefficient and absorption were calculated. the linearity relationship between the peak current and concentration of naphthol isomers was study by linear sweep voltammetry（LSV） with semi-derviative technique. Linear equations are: Ipa（μA） =-80.73- 3.21c（μmol/L）, rα-N = 0.9957; Ipa（μA） =-82.53-2.45c（μmol/L）, rβ-N = 0.9951, the detection limit of α-N is 7.13×10-8 mol/L and β-N is4.84×10-8 mol/L. Investigate the selective and service life of the modified electrode. |
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