The Research And Application Of Estrogen Residue Detection Technology

With the prosperity and development of industrial society, the human is increasinglyexposed to estrogen environment. The estrogen cause varying degrees of harm to humans andanimals directly or indirectly, even lead to cancer and deaths. In2000, the "environmentalhormones affect human health mechanism" of the National Natural Science Foundation ofChina was bidding as the key projects in China formally launched, and a large-scale study ofhormone-like substances in the environment was started. To date, about the national testingstandard of estrogen not perfect, it is necessary to establish a rapid and sensitive means of traceamounts of estrogen detecting, in order to achieve long-term estrogen surveillance.In this thesis, a study of work in the following areas:First, we established HPLC method to achieve the sensitive and accurate detection ofestradiol, estriol, ethinyl estradiol, estrone and diethylstilbestrol. Under the bestchromatographic conditions, the standard curve of the above five kinds of estrogens was set up,R2≥0.9992. With5sets of parallel experiments of samples, the relative standard deviation isless than2.5%. By spiking experiments with ducks, geese, fish, the experimental results showedthat the recoveries were between87.1%~100.1%with the method. Therefore, based on themethod described above, we detected the15samples of ducks, geese and fish, which comefrom the five different regions of Zhejiang, Jiangsu. The results show that the method with thehigh sensitivity, simple sample preparation good recoveries and reproducibility, will be suitablefor detection of livestock and aquatic products.Second, based on the electrical conductivity, adsorption and bio-compatibility ofnanographene, the nanographene-based tyrosinase biosensor was constructed. In this study, weused TEM and SAED characterized the graphene prepared by chemical reduction. By mixingtyrosinase, nanographene and chitosan in suitable proportion, then we can prepareGR-Tyr-CS/GCE electrode. Subsequently, the GR-Tyr-CS/GCE electrode was scanned from-0.3to+0.6V to obtain the background signal. Then, by scanning in a certain concentration ofBPA to optimize the pH and temperature, the detection of BPA was in the range of7.5×10-8~2.5×10-6mol L-1, R2=0.997, with a low detection limit of2.18×10-9mol L-1(S/N=3). Thiswork will provide a sensitive, rapid and simple detection method of BPA residues.Third, with the good biocompatible, large surface adsorption and excellent electrontransport properties of nanographene-gold complexes, and the catalytic oxidation and reduction of tyrosinase, we prepared electrochemical biosensor. After using the techniques of TEM,Raman, EDS to characterize graphene/gold composites, we constructed GR/Au-Tyr-CS/GCE.Then the GR/Au-Tyr-CS/GCE electrode was scanned in the solutions of the substance as thebackground signal. Then, by scanning in a certain concentration of BPA to optimize the pH andtemperature, the detection of BPA in the range of2.5×10-8~3×10-6mol L-1, the linearregression equation was Ip=3.156C+11.437, R2=0.998, with a low detection limit of1.64×10-8mol L-1(S/N=3). The work developed a rapid and effective test for BPA.