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Assessing and monitoring the quality of therapeutic mAb products

Question: Which analyses should be part of mAb characterization? I need to ensure the quality and consistency of my mAbs. Do you have any advice on which analyses I should conduct for proper mAb characterization? Answer: For several years, monoclonal antibodies (mAbs) have been the fastest-growing type of pharmaceutical molecules [1]: More than half of […]

Latest in: Analysis of Host Cell Protein See all

ELISA kit for plant based expression system

Quantifying HCP impurities in uncommon expression systems

Question: We use a plant-based expression system to produce our immunotherapy-based biologics. Unfortunately, since the expression system is quite unusual, commercial

Oct 29. 2021 | Sai Sindhu Thangaraj |

How to select an HCP ELISA with sufficient coverage for regulatory documentation

Question: How do I choose the best ELISA kit for my biologic? In other words, I would like to select the impurity assay with the highest coverage of the process HCPs, not only for harvest samples but also for the HCP impurities in the purified drug substance. Answer: Host Cell Protein (HCP) analysis is essential in development and regulatory documentation of biologics. Since specific

Aug 25. 2021 | Ejvind Mørtz |
Why mAbs call for orthogonal HCP analysis techniques

Critical reasons why mAbs call for orthogonal HCP analysis techniques

Question: We produce a monoclonal antibody (mAb) product, and our HCP ELISA shows low ppm levels. Recently, I heard that regulatory

May 21. 2021 | Thomas Kofoed |

Latest in: Analysis of Biopharmaceuticals See all

Speedy and detailed protein ID of SDS gel bands

Question: Can I identify hundreds of gel bands in a few days? The biopharmaceutical company I work for consistently uses SDS PAGE and Western Blotting to check protein expression. But this means we spend a great deal of money on antibodies, which I feel may be unnecessary. In addition, we would like to identify several unknown proteins in the gels, possibly degradation

Jun 9. 2020 | Thomas Kofoed |
mAb analysis by peptide mapping

Assessing and monitoring the quality of therapeutic mAb products

Question: Which analyses should be part of mAb characterization? I need to ensure the quality and consistency of my mAbs. Do you

Nov 25. 2019 | Thomas Kofoed |
1000 proteins quantified in e. coli mock lysate - HCP

Simple way to perform label-free quantification of Host Cell Proteins

Question: How can I improve label-free quantification of HCP? I find it difficult to get an accurate label-free quantification of Host Cell

Jun 25. 2018 | Ejvind Mørtz |

Latest in: Analysis of Amino Acid in protein See all

Use triplicate AAA to find the correct concentration of your protein standard

Why you need accurate concentration determination of protein standards

Question: How do I quantify my protein standard? How do I quantify my protein standard? Is it true that if done incorrectly,

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

Determine the Molar Extinction Coefficient of protein in 3 small steps

Question: How do I determine the molar extinction coefficient of my protein? I have a purified protein that I would like to

Nov 15. 2016 | Thanh Ha Nguyen |
Amino Acid analysis

4 things to remember about Amino Acid Analysis of proteins & peptides

Why perform Amino Acid Analysis? Amino acid analysis of proteins is a method to determine the absolute amounts of individual amino

Sep 23. 2016 | Ejvind Mørtz |

Latest in: 1D & 2D Electrophoresis See all

Speedy and detailed protein ID of SDS gel bands

Question: Can I identify hundreds of gel bands in a few days? The biopharmaceutical company I work for consistently uses SDS PAGE and Western Blotting to check protein expression. But this means we spend a great deal of money on antibodies, which I feel may be unnecessary. In addition, we would like to identify several unknown proteins in the gels, possibly degradation

Jun 9. 2020 | Thomas Kofoed |
2D PAGE preparation for MALDI ISD

1D SDS PAGE versus 2D PAGE. Any recommendations?

Question: Should I use 1D or 2D SDS PAGE? I'm interested in isolating and identifying cell surface receptor proteins. In my experience, they

Sep 18. 2016 | Ejvind Mørtz |

How much protein should I load for protein identification by mass spec

Question: How should I prepare my samples for 2D electrophoresis? How should I prepare my samples for 2D electrophoresis, and how much protein should I load to get protein ID by the mass spec? Answer: First, it is essential to know that protein samples for 2D PAGE should not contain high salt concentrations, ionic detergents like SDS, or cellular debris and DNA from cell

Jun 8. 2016 | Ejvind Mørtz |

Latest in: Bioinformatics See all

Protein molecular weight calculator

GPMAW lite – Protein Sequence Calculator (and much more)

When working with proteins, you often need to make simple bioinformatics calculations on a specific protein sequence - and for

Apr 10. 2017 | Thomas Kofoed |
protein mw calculation

Useful Protein Molecular Weight Calculator – kDa to pmol/µg

Protein molecular weight calculator kDa How do you quickly convert protein size measured in kDa or microgram into picomole - and

Nov 10. 2015 | Ejvind Mørtz |

Latest in: Database Searching & Protein Identification See all

Speedy and detailed protein ID of SDS gel bands

Question: Can I identify hundreds of gel bands in a few days? The biopharmaceutical company I work for consistently uses SDS PAGE and Western Blotting to check protein expression. But this means we spend a great deal of money on antibodies, which I feel may be unnecessary. In addition, we would like to identify several unknown proteins in the gels, possibly degradation

Jun 9. 2020 | Thomas Kofoed |
Protein molecular weight calculator

GPMAW lite – Protein Sequence Calculator (and much more)

When working with proteins, you often need to make simple bioinformatics calculations on a specific protein sequence - and for

Apr 10. 2017 | Thomas Kofoed |
Mass spectrometry analysis of protein

Common protein contaminants in mass spectrometric protein ID

Questions: Why was Keratin identified in my 1D gel band? Is the Keratin determined by the protein identification service in my 1D

Jun 3. 2016 | Ejvind Mørtz |

Latest in: mAb analysis See all

Why mAbs call for orthogonal HCP analysis techniques

Critical reasons why mAbs call for orthogonal HCP analysis techniques

Question: We produce a monoclonal antibody (mAb) product, and our HCP ELISA shows low ppm levels. Recently, I heard that regulatory

May 21. 2021 | Thomas Kofoed |

Investigation of ubiquitin in purified antibody products

Question: Should we worry about ubiquitin in our mAb? Our process-specific HCP ELISA did not detect Host Cell Proteins (HCPs) in our purified monoclonal antibody (mAb). However, mass spectrometry-based HCP analysis identified ubiquitin in low-ppm amounts. Do you have any suggestions for why the Protein A purification did not remove it? Why did ELISA not detect it? And should we worry about its

Mar 30. 2021 | Ejvind Mørtz |
mAb analysis by peptide mapping

Assessing and monitoring the quality of therapeutic mAb products

Question: Which analyses should be part of mAb characterization? I need to ensure the quality and consistency of my mAbs. Do you

Nov 25. 2019 | Thomas Kofoed |
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