Study On Novel Analysis Methods For Environmental Drug Residues By Capillary Electrophoresis

Capillary electrophoresis?CE?as a new type of liquid phase separation technology,is often used in the detection of residual drugs in environment.This technology has advantages of rapid,high efficiency and multiple separation modes.In order to solve the problem of low sensitivity of the UV detector,an effective way is to use the off-line or on-line sample enrichment method combined with the CE.Such enrichment technology has been rapidly developed in recent years duing to its simplicity,convenience,low cost and no need to transform commodity instruments.The paper starts with the sample pretreatment and compression and enrichment on the column.Three kinds of estrogenic hormones and five kinds of sulfonamides are used as target compounds.The dual-cloud point extraction method and on-line transient enrichment technology are deeply studied.It has achieved good results and broadened the application scope of CE.The details are as follows:Chapter 1:IntroductionThis chapter mainly introduced the summary of capillary electrophoresis,capillary electrophoresis sample enrichment technology,reviewed the influence of residues of estrogenic hormones and sulfonamides on the ecological environment and human health and its research progress,and expounded the significance of this article.Chapter 2:Dual-cloud point extraction-micellar electrokinetic capillary sweeping method for determination of estrogenic hormones residuesIn this chapter,the combination of dual-cloud point extraction and micellar electrokinetic capillary chromatography was used to establish a high efficient and sensitive separation and analysis method of estrogens?hexestrol,diethylstilbestrol and dienestrol?residues in environmental water samples.The non-ionic surfactant Triton X-114 was used as extractant and the NaOH solution was used as back-extractant.The samples were subjected to dual-cloud point extraction in this experiment.The parameters affecting the extraction efficiency and MEKC separation were optimized.Under the optimal conditions,the detection limits?S/N=3?of the three estrogens were 2.2×10^-9 mol/L,3.0×10^-9 mol/L and 6.3×10^-9 mol/L,respectively.The method was environment-friendly and non-toxic,eliminated the influence of the surfactant in the enrichment phase on capillary electrophoresis separation,and did not require expensive sample injection devices,satisfactory and reliable analysis results were obtained.Chapter 3:Capillary zone electrophoresis online transient enrichment of sulfonamidesIn this chapter,a micelle to solvent stacking?MSS?enrichment method was developed for online transient enrichment of five kinds of sulfonamides?sulfamethazine,sulfathiazole,sulfamonomethoxine,sulfadiazine and sulfamethoxazole?was established using anionic surfactant sodium dodecyl sulfate?SDS?as an instantaneous extraction of micelle solution plugs,combined with capillary zone electrophoresis?CZE?for separation analysis.Experiments were conducted to examine the conditions of CZE separation and the factors influencing the on-line transient concentration of samples.This method was simple and quick to operate and was 8 to 10 times higher than the classic CZE peaks.It provided a new idea for the residue detection of these drugs in environmental water samples.This dissertation successfully combined off-line and online enrichment technology with capillary electrophoresis to provide new solutions and ideas for the monitoring of environmental drug residues.