ovalbumin and 2-aminoacridone

We outline simple methodology for the rapid and selective analysis of 2-aminoacridone (2-AMAC) derivatised oligosaccharides by matrix-assisted laser desorption/ionization mass spectrometry. This involves the addition of small amounts of lithium chloride to the matrix before evaporation of solvent and crystallization. Signals mainly attributed to proton, sodium and potassium adducts are suppressed to a great extent, and a single signal due to (M + Li)+ is observed. This technique is rapid and is most useful for the direct analysis of complex glycan mixtures, after derivatization with 2-aminoacridone and without separation of the individual components.

Topics: alpha-L-Fucosidase; Aminoacridines; Cations; Chromatography, High Pressure Liquid; Crystallization; Fluorescent Dyes; Lithium; Molecular Weight; Oligosaccharides; Ovalbumin; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

The fluorophore 2-aminoacridone has been used to label a number of branched oligosaccharides previously released from various glycoproteins. Complex glycans were derivatized via their reducing end with this fluorophore by a Schiff's base mechanism followed by reduction to a secondary amine using sodium cyanoborohydride. This process of derivatization was carried out efficiently and in a nonselective manner over a period of 30 min at 90 degrees C. The resulting derivatives were separated with high resolution by capillary electrophoresis using borate buffer, containing taurodeoxycholate, as the separation buffer. The method described does not require the removal of sialic acid residues prior to derivatization, so that treatment of glycans with N-acetyl neuraminidase provided useful and additional structural information. Attempts have also been made to relate the electrophoretic mobility of branched oligosaccharides with their molecular volume.

Topics: alpha-Fetoproteins; Aminoacridines; Animals; Carbohydrate Sequence; Cattle; Chickens; Electrophoresis, Capillary; Fluorescent Dyes; Linear Models; Mannose; Molecular Sequence Data; Molecular Structure; N-Acetylneuraminic Acid; Oligosaccharides; Ovalbumin; Polysaccharides; Sialic Acids; Time Factors