The Research Of High Performance Capillary Electrophoresis Methods For Chlorophenols Detection

Capillary electrophoresis(CE)is a liquid phase analysis technology in which a capillary is used as a separation channel and a high voltage electric field is used as a driving force.It has the advantages of high separation efficiency,short analysis time,and low sample/reagent consumption.CE has a variety of different separation modes,providing different options for sample separation.In addition,CE has a unique on-line enrichment function.Now CE has been widely used in many fields,such as medical science,environmental monitoring,product quality inspection.Chlorophenols(CPs)used as intermediates in dyes,plastics and pharmaceutical production,fungicides and preservatives for cosmetics have been widely used in industry and are a kind of environmental pollutants of widespread concern.In this thesis,we explored the application of CE technology in the detection of CPs in environmental water samples and cosmetics.The sample pretreatment technology of DLLME was combined with CE to detect CPs in environmental water samples.The on-line enrichment technology of CE was also explored for the detection of CPs in environmental water samples and cosmetics.Main contents are as follows:In Chapter 1,basic principles and separation modes of CE as well as sample pretreatment enrichment and online enrichment techniques are summarized.the application of capillary electrophoresis in the detection of chlorophenols in environmental water samples and cosmetics is introduced.In Chapter 2,the separation mode of capillary zone electrophoresis(CZE)combined with sample pretreatment technology of DLLME was used to detect 5 CPs in environmental water samples: 2-chlorophenol(2-CP),4-chlorophenol(4-CP),2,4-dichlorophenol(2,4-DCP),2,6-dichlorophenol(2,6-DCP)and 2,4,6-trichlorophenol(2,4,6-TCP).The separation conditions of CE and the pretreatment conditions of DLLME were investigated.Under the optimal conditions,5CPs achieve baseline separation within 7.5 min.The enrichment factor(EFs)of 5CPs were between 15~193,and the limits of detection(LODs)were 0.31~0.75 ?g/L,respectively.The method DLLME-CZE was successfully applied to the detection of CPs in real water samples and the results were satisfactory.In Chapter 3,five CPs(2-CP,4-CP,2,4-DCP,2,6-DCP and 2,4,6-TCP)in environmental water samples were detected by on-line enrichment with CZE-field amplified injection(FASI).The factors affecting separation and enrichment were investigated.Under the optimal conditions,the five CPs achieve baseline separation within 5 min.The LODs of 5 CPs in tap water and lake water were 0.0018~0.019 mg/L and 0.0089~0.029 mg/L,respectively.The EFs of 5CPs were between 9~43 and the result is satisfactory.In Chapter 4,a method for the determination of hexachlorophenol(HCP)in cosmetics by CZE combined with high performance liquid chromatography(HPLC)was established.The electrophoresis separation conditions were optimized,and the seperation of HCP occurred within 4 min.The LODs and the limits of quantitation(LOQs)were 0.06 mg/L and 0.19 mg/L,respectively.The method was successfully applied to the detection of HCP in cosmetics.The recovery rate was between 90.0% and 96.4%,and the results were satisfactory.Compared with the national standard HPLC method,the method is simple and rapid,and the reagent consumption is small,which can be a good alternative to HPLC.In Chapter 5,a sweeping-micellar electrokinetic chromatography(sweeping-MEKC)method was established to detect bithinonol,pentachlorophenol(PCP)and 2,4,6-trichlorophenol(2,4,6-TCP)in cosmetics.CE conditions affecting the separation and enrichment of the sample were optimized.Under the optimal conditions,the enrichment factor of the method was 57~76,and the LODs of the three CPs was 0.0061~0.024 mg/L.The method was applied to the detection of these CPs in cosmetics,and the recovery rate was between 79.7%~121.3%.