Study On Novel Analysis Methods For The Determination Of Trace Fluoroquinolones Residue In Food Samples

Chapter1: The significance and headways trend of the health laboratorytechnologies for the determination of some fluoroquinolones （Gatifloxacin,Norfloxacin, Levofloxacin） were introduced respectively; The quantitative basis andthe principles for three new analysis methods of them were also introduced briefly inthis topic.Chapter2: A novel resonance fluorescence techniques was established for thedetermination of trace gatifloxacin. It was based on the fact that oxidation ofrhodamin6G by hydrogen peroxide and Cu（II） was inhibited by gatifloxacin inTris-HCl buffer medium and in presence of cetyltrimethylammonium bromide.The linear regression equation was9.8×10^-3-1.75μg mL1, and the correlationcoefficient r=0.9993, and the limit of detection was2.9ng mL^-1, the averagerecovery was101.8%for gatifloxacin. The present method had been applied to thedetermination of trace gatifloxacin in milk and biological fluids, the obtained resultswere in good agreement with those obtained by HPLC.Chapter3: In HAc-NaAc buffer solution and the presence of sodiumdodecylbenzene sulfonate （SDBS）, NOF can reaction with Y³⁺and Tb³⁺to form abinuclear complex, which results in significantly enhanced of the resonance Rayleighscattering （RRS） intensity of the system. The maximum RRS wavelength is located at365nm. The enhanced intensity （ΔI） of RRS at365nm was proportional to theconcentration of NOF. Under the optimum condition, the determination linear rangeand the detection limits of this method are1.3×10^-9-3.5×10^-7mol L^-1and4.1×10¹⁰mol L^-1for NOF. RSD were in the range of1.73﹪-3.32﹪. This method is simple and sensitive, The NOF in milk samples were analyzed by the proposedmethod with satisfactory results.Chapter4: A novel method for the determination of LVFX was developed basedon the enhancement of RRS of sodium tungstate （Na₂WO₄）-methyl violet （MV）-Levofloxacin （LVFX） system. In the Tris-HCl buffer solution, LVFX react with WO42-and MV+to form the ternary ion-association complexes, which results in significantlyenhancement of resonance rayleigh scattering of system. The enhanced intensity ofRRS at374nm is proportional to the concentration of LVFX in the range of2.5×10^-8-3.0×10^-6mol L^-1. The linear regression equation was I=38.23c(10^-7mol L^-1)^-141.32，the correlation coefficient was0.9992and the detection limit was7.4×10^-9mol L^-1. It was applied to determine trace LVFX in samples with satisfactory results.