IMG_4746A first step in understanding glycosylation

Much of the information we gather through protein research is to help you develop batches of products that are consistent and stable. These are essential ingredients to developing drugs with predictable and effective behaviour.

One such piece of information is sialic acid content, something that can vary considerably between batches. Some sialic acids are an essential part of your protein’s structure, whilst others are undesirable. It’s important to be able to differentiate between the two

We carry out all our glycosylation research services in-house, which means we don’t outsource any of it.

And we don’t rely on just one technique but cross-check our findings using several different methods to ensure that our results are correct. This also allows us to look at slightly different aspects of your research or drug development question.

As with monosaccharide analysis, measuring sialic acid content is a simple process. Our biopharmaceutical customers usually want it done in conjunction with more complex processes as part of a bigger research program.

Analyzing sialic acid content is a key requirement of ICH Q6B.

Technical information

Sialic acids are negatively charged, terminal monosaccharides and are important structural constituents of many glycans. The number of sialic acids impacts on the activity and serum stability of many glycoproteins. As different types of sialic acid can be incorporated into the glycan structure, it’s important to be able to determine the presence of correct versus undesired sialic acid structures.

Once sialic acids are released by acidic hydrolysis, we analyze them by HPAEC-PAD. We can look at N- and O-linked glycans carrying sialic acids by using HPAEC-PAD, LC-ESI-MS or MALDI-MS.

The composition of glycans attached to a protein can further be determined by monosaccharide analysis.

Finally, we can visualize the structural heterogeneity of a glycoprotein using IEF or 2D PAGE. This is because sialic acids will lead to a shift in the pI of the glycoprotein, which is then observable.

Your contact for Sialic Acid at Protagen Protein Services GmbH


Dr. Marcus Mreyen

Director Business Development
Our business development team will be happy to assist you with your project.

Phone: +49 (0) 231 9742-6100