17 articles

How to characterize antibody glycosylation by HILIC-MS

Question: What is N-glycosylation and how do I characterize the N-glycosylation of my antibody? Is it possible to compare batch-to-batch variations?   Answer: Glycosylation is...

Mar 4. 2019 | Thomas Kofoed | 0
1000 proteins quantified in e. coli mock lysate - HCP

Is there a simple way to perform label-free quantification of Host Cell Proteins?

Question: I find it difficult to get an accurate label-free quantification of Host Cell Proteins with LC-MS. It also seems that...

Jun 25. 2018 | Ejvind Mørtz | 0

What are “Jackpot HCPs” and why do I need a “lucky goat” to get a precise result in my HCP ELISA?

Question: I tested two different HCP ELISA kits on my biopharmaceutical. Why do they give different results and which one is...

May 28. 2018 | Anette Draborg | 0

Quickly compare HCP in different process steps, without setting up an ELISA

Question: I have spent days trying to set up a useful ELISA assay for detecting Host Cell Proteins (HCPs) in my process samples. I'm...

Apr 10. 2018 | Ejvind Mørtz | 0
HPLC analysis of process related impurities by reverse phase mass spectrometry ( LC-MS analysis )

How to identify peaks observed by UV-HPLC in stability studies

Question: We have developed a Reversed-Phase (RP) UV- HPLC chromatography method. It is used for stability studies of our new pharmaceutical protein. How do we...

Jan 24. 2018 | Thomas Kofoed | 0
What is SWATH?

What is SWATH and why is it an advantage for Host Cell Protein analysis?

Host Cell Proteins (HCPs) in protein biopharmaceuticals can be analyzed by mass spectrometry - for both identification and quantification of...

Jun 22. 2017 | Thomas Kofoed | 0

4 reasons why Amino-terminal sequencing of mAbs should be done by Edman degradation

Question: How do I obtain the N-terminal sequences of the heavy chain and light chain of my monoclonal antibody?   Answer: mAb N-terminal sequence...

Apr 26. 2017 | Ejvind Mørtz | 0
Antibody characterization

How to: Make sure that Ile/Leu are correctly assigned by de-novo sequencing of your antibody

Question: I was told that de-novo sequencing by mass spectrometry is not able to distinguish between Ile and Leu residues in my...

Mar 22. 2017 | Fen Yang Reske-Nielsen | 0
Application note - mAb

What purity is required for de-novo sequencing of my antibody?

Question: My monoclonal antibody is not 100% pure, what is the purity required for de-novo sequencing?   Answer: We typically observe two types of protein impurities in...

Mar 20. 2017 | Fen Yang Reske-Nielsen | 0
100% sequence coverage map of antibody

Antibody de-novo Sequencing by Mass Spectrometry: How to get 100% sequence coverage

Question: Is it possible to perform a de-novo sequencing of my purified monoclonal antibody without the hybridoma cells?   Answer: Yes! – Your purified antibody can...

Mar 17. 2017 | Fen Yang Reske-Nielsen | 0

Reasons why you need accurate concentration determination of your protein standards

How do I quantify my protein standard? Have you ever questioned the quantitative data you get from Bradford, Lowry or BCA protein quantification...

Jan 18. 2017 | Thomas Kofoed | 0
Extinction coefficient protein concentration

How to determine the Molar Extinction Coefficient of your protein (in 3 small steps)

Question: I have a purified protein that I would like to quantify accurately in my lab using 280 nm UV measurement...

Nov 15. 2016 | Thanh Ha Nguyen | 0
Analysis method for Mw HCPs (small HCPs) below 20 kDa

Identification of small host cell proteins (low Mw HCPs)

Question: Could you suggest an analysis method to detect low Mw HCPs (small HCPs) below 20 kDa? I work on a drug...

Oct 11. 2016 | Ejvind Mørtz | 0
Protein scientist at Alphalyse

3 steps to identify and quantify HCP in a drug substance homolog from a host cell

Question: My HCP antibodies show a reaction towards a drug substance band in my Western blot. Is it possible that it is...

Sep 5. 2016 | Rikke Raaen Lund | 0

Identification of proteolytic degradation of recombinant protein

Question: I purified a recombinant protein and analyzed it by 1D SDS PAGE. In addition to the intact protein (52...

May 9. 2015 | Ejvind Mørtz | 2

Assessing the stability of a protein drug substance and formulated drug product

After protein purification, an important issue is the stability of a protein drug substance and formulated drug product. Stability assays...

Oct 21. 2013 | Ejvind Mørtz | 1

Mass Spectrometry for Host Cell Protein monitoring and control in pharmaceutical process development

Mass spectrometry based Host Cell Protein identification and quantification Here the Mass Spec Host Cell Protein (HCP) assay is applied for...

Oct 2. 2009 | Ejvind Mørtz | 2
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