Establishment And Application Of Two-dimensional Ion Chromatography

Since the commercial ion chromatography(IC)was introduced in 1975,it has become the first choice for the analysis of ionic compounds due to its advantages of fast analysis speed,good selectivity,high sensitivity,and the ability to realize simultaneous analysis of multiple components.With the application of electrochemical detection and the appearance of new stationary phases,IC has an absolute advantage in the analysis of polar organics,and even can separate polar,ionic and neutral compounds and compounds with different chromatographic properties simultaneously.The application of ion chromatography has been greatly expanded,including extensive applications in the fields of environmental monitoring,food and beverage,semiconductor,energy and chemical and metabolomics.With the expansion of application fields,the types and compositions of samples are diverse.Conventional single-column/one-dimensional IC often cannot provide sufficient separation efficiency and has some limitations.Therefore,it is necessary to eliminate the interference of matrix,enrich trace substances,and accurately analyze a variety of different components at the same time,so as to establish a multidimensional ion chromatography analysis system with high sensitivity and high selectivity.In this paper,two different types of two-dimensional IC systems and a threedimensional IC system are constructed with different columns and detectors on the basis of conventional single column analysis by using valve-switching technology.The interference between the matrix and the components has been successfully eliminated,and the simultaneous analysis of multiple components is realized.This paper mainly includes the following research contents:(i)A two-dimensional ion chromatography(2D-IC)system for simultaneous determination of 20 amino acids and 7 sugar alcohols in beer was established;(ii)A two-dimensional ion chromatography system(2D-IC)for simultaneous determination of organic acids and glucose in Escherichia coli was established;(iii)A three-dimensional ion chromatography(3D-IC)was successfully constructed for simultaneous determination of amino acids,organic acids and sugars in Clostridium thermocellum culture solution.