BioQuant Monosaccharide Standard

The monosaccharide standard is a quantitative standard comprised of a mixture NIST-F and USP traceable monosaccharides including glucosamine (GlcN), galactosamine (GalN), galactose (Gal), mannose (Man), glucose/dextrose (Glc) and fucose (Fuc).

Form: Dry. Dried by centrifugal evaporation from an aqueous solution.

Amount: 10 nmol each of 6 monosaccharide standards

HPLC Analysis of the Monosaccharide Standards
HPLC analysis of 2-AA labeled monosaccharides is a robust method for determining monosaccharide levels in your glycoprotein sample.
1. Each monosaccharide has a different fluorescence yield per nmol. A standard curve of monosaccharide concentration versus fluorescence needs to be determined.

2. Free dye is not removed from the samples after 2-AA labeling to ensure no monosaccharides are lost in a dye clean-up stage. Free dye elutes as a large off-scale peak at about 15 minutes and also several large peaks after 28 minutes.

3. N-acetylglucosamine and N-acetylgalactosamine are both de-N-acetylated during the acid hydrolysis step of this process to produce glucosamine and galactosamine respectively.

4. Glucosamine is subject to an approximate 4 % epimerisation resulting in mannosamine. Mannosamine elutes immediately before the galactosamine peak, with no baseline resolution.

5. Galactosamine also produces an epimer peak, typically smaller than 2 %. However this epimer peak often elutes with the free dye peak.

6. The use of xylose as an internal standard allows samples to be compared directly. This allows compensation for any pipetting/sample preparation errors that may have occurred during sample processing.

7. Sample stability – we recommend keeping labeled samples in the freezer at -20 °C if you intend to store them for longer than one week.

HPLC profile of 2-aminobenzoic acid (2-AA) labeled mono-mix. The peak between 2 to 3 min is free dye.