Study On The Analytical Methods Of Trace Carbohydrates And Their Derivatives In Bio-samples By Capillary Electrophoresis

1.PrefaceCapillary electrophoresis(CE)is a fast-developing and widely-used analytical technique,possessing the advantages of high separation efficiency,low reagent consumption,high degree of automation,good reproducibility and low cost.This chapter briefly introduces the basic theories and applications of CE,the development of electrophoretic online enrichment methods,and analytical methods of CE for carbohydrates in recent years.In this paper,combining high separation efficiency of CE with good versatility of capacitively coupled contactless conductivity detection(C4D)or high sensitivity of amperometric detection(AD),as well as on-line enrichment technology.The developed CE methods have accomplished the trace analyses of the main sialic acids and typical carbohydrates,and then were applied to analyze biological samples.The developed methods could directly determine above target analytes without need of derivatization process,providing such advantages as short analytical time,high detection sensitivity,simpleness and environment-friendly.2.Direct determination of two major sialic acids in biological samples by MCRB/CE-C4D methodA sensitive and fast method of CB-C4D coupled with a transient moving chemical reaction boundary stacking technique(MCRB)was developed for the simultaneous determination of two major sialic acids(SAs),N-acetylneuraminic acid(NANA)and N-glycolylneuraminic acid(NGNA).A series of experimental parameters affecting electrophoretic separation,detection sensitivity and hydrolysis efficiency of SAs were investigated.Under the optimum conditions,NGNA and NANA could be well separated with common monosaccharides,disaccharides and other potentially coexisting inorganic and organic anions.This developed method has been applied to analyze the total contents of SAs liberated from saliva,milk and milk powder.In terms of its low LODs(1.4-2.2 ng/mL),good linearity(r?0.9990),acceptable recovery(90%-107%),and reliability of acid hydrolysis step,this MCRB/CE-C4D is a simple,easy-to-detect,sensitive,and environmentally friendly method of sialic acid analysis.This method doesn't require derivatization and provide a potential new approach for the analysis of NANA and NGNA in body fluids and dairy products.3.Direct determination of iconic carbohydrates in noninvasive body fluid by FASS/CE-AD methodA combination of field-amplified on-line enrichment technology and CE-AD technology was developed to establish a rapid,sensitive and low-cost analytical method for glucose.In this study,a series of experimental parameters for the separation and detection of glucose and its potential coexisting interferences were studied.Under the optimum experimental conditions,glucose and galactose can be well separated from common carbohydrates as well as other potential coexisting substances.This method has been applied to the analysis of glucose in noninvasive saliva,possessing high sensitivity(LODs:4.2-7.2 ng/mL),good linearity(r>0.999)and acceptable recoveries(90%-114%).Due to its simple,safe,sensitive and environmentally friendly,the FASS/CE-AD method could provide a potential new method for the sensitive detection of typical carbohydrates in noninvasive body fluids.