Application Of Spectrofluorimetric Methods In Soil Cd-contaminated Assessment

In this dissertation, feasibility study of determining the activity of earthworm microsome Ethoxyresorufin O-deethylase (EROD) by fluorimetry was discussed. The sensitivity of the measurement method was improved by optimizing a series of experimental parameters, and the experimental result was satisfactory.In the first section of the dissertation, at the beginning, the progress of environmental pollution including present state, hazard of soil environmental pollution was summarized; the significance and research technique for diagnosing ecotoxicity of the soil pollutant was introduced as the emphasis.Then, the definition, classify, the measuring method of recommended the biomarker, and the research advance cytochrome P450in diagnosing ecotoxicity of the soil pollutant were discussed in detail. Finally, the fluoremetry principle was briefly introduced.The second section of the dissertation is the main part of the whole thesis. A spectrofluoremetric method for measuring earthworm microsome EROD was proposed based on the principle in which NADPH starts EROD catalyzing zymolyte into resorufin with fluorescent light at oxygenation condition. The sensitivity of fluoremetric method was improved by means of optimizing physical and chemical parameters. Under optimized experiment condition, linear range was0.5-20pmol/mL with detection limit of0.04pmol/mL, the slope of optimized standard curve is greater than that of without optimization. The relative standard deviation for the method was1.1%at10pmol/mL level (n=11). The proposed method has been applied to the diagnosing ecotoxicity of the soil pollutant with satisfactory results.The third section was the summary of the experiment. The prospect of application of fluorescent technique and the feasibility of EROD as biomarker for diagnosing Cd-contaminated soil within low dosages range was described.