Capillary electrophoresis(CE) equipped with chemiluminescence (CL) detection has attracted a great deal of attention as a high-performance separation and detection system. [1][2][3][4] We also analyzed many types of sample, including metal ions, metal compounds, amino acids, peptides, proteins, nucleic acids, saccharides, phenolic compounds, fluorescence compounds, and liposomes, using these systems. [5][6][7] We have determined the significant features of CE with CL detection systems through our previous research. 8,9 Naturally, while absorption and fluorescence detection in CE are carried out in an on-capillary manner, CL detection is brought about by endcapillary (postcolumn) detection. That is, CE with CL detection possesses a very interesting and useful "micro-environment area" for reaction/detection at the tip of the capillary outlet. Trace amounts of sample and reagents are delivered quantitatively and mixed reproducibly at the tip of the capillary outlet (micro-environment area), leading to useful and unique CL responses with high sensitivity.Saccharides are among the most important biological molecules in the living body. The compositional formulas of saccharides are simple, as they consist mainly of carbon, hydrogen, and oxygen. However, their molecular structures are very complicated. This complexity in the molecular structure is produced through the various directions of hydroxyl groups in the molecule. There have been many investigations of methodologies to derive information regarding the molecular structures of saccharides, i.e., molecular recognition of saccharides. 10,11 Boronic acids form cyclic esters with saccharides, particularly with those comprising cis-diol groups. [12][13][14] The interaction between boronic acids and saccharides has been used for molecular recognition of saccharides. To derive information regarding the interaction between boronic acids and saccharides, conventional procedures for molecular recognition require specific chemical reactions, such as polymerization and derivatization.In our previous study, 15 we found that the enhancing effect of p-iodophenylboronic acid on luminol-hydrogen peroxidehorseradish peroxidase CL reaction decreased in the presence of saccharide, and we proposed a system to take advantage of the micro-environment area of the CE-CL detection system for molecular recognition of saccharides. The decrease in CL could provide direct information regarding the interaction between piodophenylboronic acids and saccharides without requiring any specific procedures. The method for molecular recognition of saccharides has the following beneficial features in comparison with conventional methods, 16,17 including CD spectra, extraction, and π-A isotherm studies: 1) high sensitivity (a trace amount of a sample specimen is used), 2) rapid analysis, 3) ease of operation, and 4) inexpensive reagents and apparatus.In the present study, to extend our knowledge regarding the molecular recognition of saccharides using the CE with CL detection system, we examined the enh...
