Research Of On-line Enrichment Capillary Electrophoresis With Amperometric Detection For Sulfonamides

Capillary Electrophoresis(CE)is a new type of liquid phase separation technique with high voltage direct current electric field as the driving force.Because of the various patterns of separation,high enrichment efficiency,so often used in trace detection of residues in food drugs.Sulfonamides(SAs)are a group of synthetic antibiotics that have played an important role as effective chemotherapeutics.Owing to their broad-spectrum activity and low cost,SAs are widely used in food-producing animals for the rapeutic,prophylactic,and growth-promoting purpose.When these animals are used as food,inappropriate abusive antibiotic-based treatments or insufficient withdrawal time would leave some SAs residues inside the slaughtered animals.These residues have been of great public concern because they can cause allergic reactions in human,and even possess the carcinogenic potency.At present,there are many methods to detect the sulfonamides,but at the same time to be able to quickly and efficiently separation of testing trace report of sulfonamides residues is relatively fewer.this also is a lot of research workers of the hot research topics.This thesis focuses on the study of the capillary electrophoresis column enrichment technology,two column enrichment technology can further improve the enrichment ratio of the sample to be tested,and the detection limit is lower.The dissertation includes 4 chapters:Chapter 1:PrefaceThis chapter presents the summary of capillary electrophoresis and its basic principle,capillary electrophoresis sample enrichment technology and researchprogress of sulfa drugs and estrogens.This chapter mainly introduces the general situation of capillary electrophoresis,capillary electrophoresis sample enrichment technology,the classification and application of the surfactant,the residues of SAs on the environment and the influence of human life and its research progress,and elaborated the selected topic significance of this article.Chapter 2:Micellar electrokinetic chromatography-sweeping method for the detection of sulfonamides residues in milk.A new method for the analysis of SAs by MEKC with anionic surfactant(SDS).Under the optimal conditions,The linearity was obtained over the range of 0.9992?0.9988?0.9997?0.9988?0.9947.The detection limits is 10-9 mol/L.Skimmed milk sample after processing into CE analysis,found that the test method can be successfully applied to the actual sample testing,simple operation,high sensitivity,detection limit within specified requirements.Chapter 3:Rapid determination of sulfonamides using micellar electrokinetic chromatography featuring sweeping and micelle to solvent stacking.Two-step stacking of organic cations by sweeping and micelle to trapping solvent stacking(MSS)was developed in acidic buffer in micellar electrokinetic chromatography(MEKC)is presented.The experimental parameters,such as the acidity and concentration of buffer systems,additives,separation voltage,detection potential and the injection time were studied for efficient and fast component separation.Under the optimized condition,MEKC on-line preconcentration technique has been developed for determining four sulfonamides in sea cucumber aquaculture water.The proposed method yielded results with good selectivity,fast analysis and good reproducibility when applied to the separation and analysis of the actual samples.Chapter 4:The detection of sulfonamides based on the capillary zone electrophoresis with reverse voltage and field amplified sample stackingUnder the optimized condition which was using 22.5 mmol/L phosphate solution 0.8 mmol/L CTAB at pH 8.70 as running buffer,18%(v/v)acetonitrile as organic additive,0.1 mmol/L NaOH as sample solvent,injection time was electrokinetic injection-13 kVx20 s.The detection limit of four kinds of drugs in this method is 10-9-10-10 mol/L,and this method satisfies the requirement of qualified.