Estimation of sialic acid in a sialoglycan and a sialoglycoprotein by capillary electrophoresis with in-capillary sialidase digestion.
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.
Taga
Atsushi
A
Faculty of Pharmaceutical Sciences, Kinki University, Higashi-Osaka, Japan.
Sugimura
Mayumi
M
Suzuki
Shigeo
S
Honda
Susumu
S
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
D011134:Polysaccharides; D012795:Sialoglycoproteins; D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid