Get enhanced impurity identification and quantification with strong specificity
Host Cell Protein (HCP) Analysis

Host Cell Protein (HCP) Analysis

Despite purification respectively polishing processes in protein preparation, it’s not possible to create proteins without host cell proteins. In addition to these process-related impurities there are also product-related impurities to be caused by protein modifications. 

Protein impurities may generate undesired side effects. So characterizing protein impurities is a key requirement of ICH Q6B. We identify and quantify all the proteins in your mixture using mass spectrometry. By carrying out a bioassay, we can also see if the impurities are influencing the efficacy. Finally, we eliminate the unwanted proteins one step at a time by focusing on the differences in their characteristics.

The process is tailored to your needs because every client’s requirements are different.

  • Testing and Demonstration of specificities
  • HCP-GAPex™ Services
  • Identification of HCPs

For demonstration of specificity high resolution 2D PAGE of respective antigens (e.g. whole cell lysate, DSP fraction) is performed. Total HCPs are visualized by sensitive silver staining. In parallel a second 2D PAGE gel is subjected to Western blotting to visualize all HCPs recognized by  respective antisera. These patterns are compared and visualized by overlay. Ideally, all HCPs visualized by silver staining are also recognized in the Western blot experiment, which would mean there are no detection gaps of the used antiserum. If detection gaps occur, we recommend usage of our HCP-GAPex™ services.

Application example for qualification of HCP antiserum:


Your Contact for HCP Analytics

please call us +49 (0) 231 9742 6100

Dr. Thomas Flad

Head of Business Development
South Germany, DACH Region


Protagen Protein Services (PPS) is a world leading CRO and recognized expert for analytical services in protein science regarding characterization, method development, validation and routine testing of antibodies, proteins, vaccines and other formates of biopharmaceuticals. Our sites are equipped with modern, state-of-the-art equipment for the analytical characterization of biopharmaceuticals regarding structure, purity, chemical modification, aggregation, particle formation, thermal stability e.g.. We offer service modules for analytcal support from research to approval regarding:

  • Developability
  • Clone Selection & Process Development
  • Extendend Characterization & Comparability
  • Stability & Release


Protagen Protein Services (PPS) is a world leading CRO and recognized expert for analytical services in protein science. More than 20 years of market experience and the comprehensive spectrum of validated analytical methods ensure the highest quality for customers in the pharmaceutical, biotech and life science industry.

PPS supports Biosimilar developers with a broad range of analytical methods and consulting in achieving and demonstrating Biosimilarity