Descriptions of Assays return to home page
HPAEC N-linked Oligosaccharide Profiling
This assay is specific for oligosaccharides linked to the amino acid asparagine on proteins, referred to as N‑linked oligosaccharides or N-glycans.
In this analysis, N-linked oligosaccharides are released from the glycoprotein using the enzyme PNGase F (N-glycosidase F) and then separated by HPLC (high performance liquid chromatography). The oligosaccharides are separated by anion exchange chromatography which separates the oligosaccharides into groups according to their negative charge. For example, oligosaccharides with different numbers of sialic acids will be separated.
This assay provides a qualitative profile, or map, of the different oligosaccharides in a sample. This is a very powerful method for comparing the N-glycosylation of different samples.
We have a specific version of this method that has been optimized for recombinant monoclonal antibodies (MAbs).
Fluorescent N-linked Oligosaccharide Profiling
This assay is specific for oligosaccharides linked to the amino acid asparagine on proteins, referred to as N‑linked oligosaccharides or N-glycans.
In this analysis, N-linked oligosaccharides are released from the glycoprotein using the enzyme PNGase F (N-glycosidase F) labeled with a fluorophore and then separated by HPLC (high performance liquid chromatography). The oligosaccharides are separated by normal phase chromatography which separates the oligosaccharides into groups according to their negative charge. For example, oligosaccharides with different numbers of sialic acids will be separated.
This assay provides a qualitative profile, or map, of the different oligosaccharides in a sample. This is a very powerful method for comparing the N-glycosylation of different samples.
We have a specific version of this method that has been optimized for recombinant monoclonal antibodies (MAbs).
O-linked Oligosaccharide Profiling
This assay is specific for oligosaccharides linked to the amino acids serine or threonine in proteins, referred to as O‑linked oligosaccharides or O-glycans.
In this analysis, O-linked oligosaccharides are released from the glycoprotein chemically using alkaline degradation and then separated by HPLC (high performance liquid chromatography). The oligosaccharides are separated by anion exchange chromatography which separates the oligosaccharides into groups according to their negative charge. For example, oligosaccharides with different numbers of sialic acids will be separated.
This assay provides a qualitative profile, or map, of the different oligosaccharides in a sample. This is a very powerful method for comparing the O-glycosylation of different samples.
MALDI-TOF Mass Spectrometric Oligosaccharide Profiling
In this analysis, oligosaccharides are released from the glycoprotein and then analyzed by mass spectrometry. Masses are determined for the different oligosaccharide structures in the pool.
Neutral Monosaccharide Analysis
This assay measures galactose, mannose, fucose, N-acetylglucosamine (GlcNAc) and N‑acetylgalactosamine (GalNAc).
Monosaccharide units are released from glycoproteins, oligosaccharides, polysaccharides or other glycans using acid hydrolysis. The individual monosaccharides can then be separated by HPLC (high performance liquid chromatography). The amount of each monosaccharide in the sample can be measured by comparing the response in the sample to a standard curve of each monosaccharide.
Sialic Acid Analysis
This assay measures N-acetylneuraminic acid (NeuAc/NANA) and N-glycolylneuraminic acid (NeuGc/NGNA), the two most common sialic acids on recombinant glycoproteins. These monosaccharides cannot be measured using the same assay as the neutral monosaccharides since they are more easily destroyed by acid, therefore require a milder acid hydrolysis.
Sialic acids are released from glycoproteins, oligosaccharides, polysaccharides or other glycans using a mild acid hydrolysis. NeuAc and NeuGc are then separated by HPLC (high performance liquid chromatography). The amount of each monosaccharide in the sample can be measured by comparing the response in the sample to a standard curve of each sialic acid.
Mannose 6-Phosphate Analysis
This assay measures mannose 6-phosphate (Man 6-P/M6P) on recombinant glycoproteins. Mannose 6-phosphate is released from glycoproteins using acid hydrolysis. Man 6-P is then identified by HPLC (high performance liquid chromatography) and measured by comparing the response in the sample to a standard curve of Man 6-P.
Galactose α1-3 Galactose Analysis
This assay measures galactose linked α1-3 to another galactose molecule on recombinant glycoproteins and other glycans. Galactose is released, enzymatically using an enzyme specific for galactose in α1-3 linkage and then free galactose is identified by HPLC (high performance liquid chromatography) and measured by comparing the response in the sample to a standard curve of galactose.
Uronic Acid Analysis
This assay measures uronic acid by releasing the monosaccharide using acid hydrolysis. Uronic acid is then identified by HPLC (high performance liquid chromatography) and measured by comparing the response in the sample to a standard curve of uronic acid.