title: Estimation of sialic acid in a sialoglycan and a sialoglycoprotein by capillary electrophoresis with in-capillary sialidase digestion.
abstract: An example of application of in-capillary derivatization for CE, obtained by using the throughout-capillary format, is presented. Introduction of a sialoglycan (N-acetylneuraminyllactose) or a sialoglycoprotein (bovine serum fetuin) sample to a running buffer (pH 5.0) containing N-acetylneuraminidase followed by application of a voltage resulted in the release of N-acetylneuraminic acid (NANA) which could be estimated by CE with UV detection. Two-step application of voltages (5 and 20 kV) was proved to be more effective for rapid estimation of the released NANA. This format (modified throughout-capillary format) allowed differential estimation of the NANA present in the sample as an impurity and the NANA released from the substrate at the picomol level, and thereby reliable micro assay of the sialidase activity. It also allowed estimation of the rate constant of this enzymatic reaction.
authors.affiliation: Faculty of Pharmaceutical Sciences, Kinki University, Higashi-Osaka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Taga
authors.forename: Mayumi
authors.initials: M
authors.lastname: Sugimura
authors.forename: Shigeo
authors.initials: S
authors.lastname: Suzuki
authors.forename: Susumu
authors.initials: S
authors.lastname: Honda
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods*; D006868:Hydrolysis; D007700:Kinetics; D019158:N-Acetylneuraminic Acid / Q000032:analysis*; D009439:Neuraminidase / Q000378:metabolism*; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism; D012795:Sialoglycoproteins / Q000737:chemistry* / Q000378:metabolism; D013056:Spectrophotometry, Ultraviolet
chemical_list: D011134:Polysaccharides; D012795:Sialoglycoproteins; D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid