| Chitosan has a high metal-chelating ability due to its amino groups and hydroxy groups. It can effectively adsorb not only metal ions but also various organics~ and also, chitosan can be dissolved in weak acid, so it be widely used. Recently, there have some reports on its electroanalytical chemical application. On the basis of previously study, we have prepared the chitosan modified glassy carbon electrode (CMGCE) and studied its adsorbability of metal and nonmetal. We have combined the good chelation, ion exchange, and adsorptive ability of chitosan and the high-selectivity of CMGCE. Thus further enlarged the application rang of chitosan on electroanalytical chemistry. The main content of this thesis as follows: 1. A new method was developed for the determination of total Fe. During the experiment C204> was used as complex agent, using its reductive affect and the instability of Fe(C202)33 to light, the method can be used to determine the total Fe in the sample. The cyclic voltammetry and cathodic stripping voltammetry were used to study the electrochemical behaviour of Fe. The UV absorption cure was used to convict the formation of chitosanH~ Fe(C2042)j. A liner response was found in the concentration range 2 X 10 8g/ml? X 107g/ml Fe with a detection limit of 1 X 108g1m1, the regress equation is yl.20+3.1143x ( r=O.997 ). A relative standard deviation (R.S.D.) of 3.67% was obtained for six determinations of 2>(107g/ml Fe3. This method can be used to determine the total iron in tap water and mineral water directly. 2. Chitosan-modified Glassy Carbon Electrode (CMGCE) was used for the determination of B( for the first time. The measurement was carried out by cathodic stripping voltammetry. The effects of several experimental parameters were studied for analytical application. We also studied the adsorption isothermal line of bromide. A liner response was obtained in the concentration range 3.2X 1O~---6.4X lO~ g/ml of Br, the regress equation is y ?.11 + 1.1098x(r0.998). In the solution of l.6X lW6g/ml Br, the relative standard deviation of six successive determination is 6.06%, while that of modified six times respectively for the same electrode is 8.60%. The detection limit was found to be 9.6 X I 0~7gIml. The method was used to detect bromide MASTER Y{E~ i c content in chemical regent and wastewater the results are satisfactory. 3. CMGCE was used for the determination of SCW for the first time. The cyclic voltanimetry, anodic adsorptive voltammetry and chronocoulometry were used to study the electrochemical behaviour and adsorptive characters of SCNTh A liner response was obtained in the concentration range 3?x l0~---9.3 x iO~ gfml of SCN, the regress equation is y2.501x+ 3.504(r0.998). The detection limit was found to be l.9x10抔Iml. The relative standard deviation was found to be 3.7% for six successive determination of 4.64X lCV7gIml SCN, while that of modified six times respectively for the same electrode is 7.0%. The method was used to detect SCN in saliva. |
