The Interface Design Of CE-ICP-MS And Its Application In Arsenic Speciation Analysis

Arsenic is a kind of non-metallic element,which is widely existed in nature.The toxicity of arsenic vary by the different speciation.In general,the determination of total arsenic content in the sample can not meet the requirements of the analysis.In order to study the biological activity and toxicity of the elements better,speciation analysis of elements must be studied.Capillary electrophoresis(CE)is a separation technique where analytes migrate through electrolyte solutions under the influence of an electric field.The advantage of the CE is fast analysis speed,high separation efficiency and small sample uptake,which is suitable for the speciation analysis.Inductively coupled plasma mass spectrometry(ICP-MS)has the advantage of multi element analysis simultaneously,low detection limit,wide dynamic range.Thus,since the first publication of CE-ICP-MS in 1995 by Olesik,the method has become a powerful tool for the element speciation analysis.In this thesis,we have studied the capillary electrophoresis,inductively coupled plasma and its coupling technique.The speciation analysis of arsenic,selenium,chromium and manganese and the application on nuclear sample based on CE-ICP-MS is reviewed by this thesis.The interface of CE-ICP-MS is designed and made.The CE-ICP-MS system,which include pneumatic nebulizer,high voltage power supply,mass flow meters and controllers,is built based on the interface.Principle block diagram and performance parameters of main components are given in this work.This system has the advantages of easy to connect and disassemble,small dead volume,etc.A method for the separation analysis of six arsenic(As C,As B,As(III),DMA,MMA)is developed based on the CE-ICP-MS system.The detection limit was 2.6-7.2ug L-1,and the relative standard de viation(n=4)of five species of arsenic compounds was 3%-8%.The method was successfully applied to determine the content of the actual sample purchased in the local market,and the recovery rate was between 80%-110%.Our results show that this method is suitable for the detection of real samples.