The Application Of Magnetic Composite In The Analysis Of Quinolones

In recent years,the existence of chemical pollutants has been a issue that is not allowed to ignore in food safety,and the most striking thing is the existing of drug residue in animal source food.Therefore,it is necessary to establish relevant monitoring methods which were used to monitor all aspects of food production,processing,reprocessing,transportation and storage.Due to the complexity of ingredients in food,which contain protein,inorganic salt,fat,etc.,these ingredients can interfere the analysis of the drug residues,so it is quite important to develop a technique of selective separation and enrichment for drug residues.Because of the simple operation,low cost and environment friendly,the magnetic solid phase extraction technology is widely used as the sample pretreatment technology.In this paper,a magnetic composite,which was used as an extractant,combined a high performance liquid chromatography method,was used to analyze quinolones in food.1.The preparation and the type of magnetic nanomaterials and magnetic nanocomposites were Summarized.At the same time,this part also simply introduces the magnetic solid phase extraction technology and its development,and enumerates the application of this technology for pharmaceutical analysis in biological samples and the water environment.In addtion,the significance and main content of this research are described.2.A sensitive and economical method for the determination of quinolone drugs in milk sample（lomefloxacin,norfloxacin,ofloxacin,perfloxacin,enrofloxacin）was established.Magnetic reduction graphene oxide was prepared,and was used as the adsorbent for the extraction of mentioned above five kinds of quinolones in milk,and then using high performance liquid chromatograph and fluorescence detector for the determination and separation of drugs.The factors affecting the performance of this method（the type adsorbent and eluent,the time of the adsorption and desorption,sample solution,etc.）were optimized.Under optimal conditions,good linerarities were abtained,the detection limit of this method is between 1 and 4 ng·L^–1;the spiked rate between 86.5 and 104.1%and the relative standard deviation is less than 5%.3.A convenient,rapid and efficient method for the determination of five quinolones in eggs was established using Fe₃O₄-MoS₂ as a magnetic solid phase extraction material and high-performance liquid chromatography with a UV-visible detector as detective method..We optimized the parameters affecting the analytical performance of this method（the adsorbent,the time of adsorption and desorption,the eluent,sample solution,pH and others）.Under the optimized conditions,good linerarities were abtained,a coefficient determination of correlation coefficients ranging from 0.9990 to 0.9997 and detection limits from 0.25 to 0.5μg·L^–1.The RSDs of the intra-and inter-day trials were less than 5%.The spiked recoveries ranged from 88.6%to 96.6%with RSDs of less than 5%.4.A novel kind of magnetic composite materials（Fe₃O₄-MoS₂-g-C₃N₄）was successfully synthesized,and was applied to magnetic solid phase extraction process,and then combined with high performance liquid chromatography（HPLC）and photo-diode array detector（PDA）for the analysis of quinolones in chicken samples.In addition,the type and amount of the adsorbent,solution pH,extraction time,and desorption conditions was optimized.Under optimal conditions,good linerarities were abtained,the correlation coefficient is0.9992-0.9997,and the detection limit is 0.5-1.0 ng·mL^–1.The method（MSPE-HLPC-PDA）was successfully applied to the analysis of quinolones in chicken.