Process-Related Impurity Analysis of Biotherapeutics

Impurity testingGyrolab® systems and immunoassays speed up the bioprocessing workflow

Process-related impurity concentrations are highly regulated in the manufacture of biologic drugs because of their immunogenic potential. Bioanalytical methods to detect and measure process related impurities must be developed carefully to characterize heterogeneous mixtures of host cell proteins (HCPs) present in samples, or the copurification of culture or process impurities such as protein A together with the biotherapeutic.

  • Heterogeneous mixtures of host cell proteins (HCPs), for example
    Chinese Hamster Ovary (CHO)-HCP, E. coli HCP, phospholipase B-like 2 (PLBL-2) and transferrin
  • Process-specific impurities
  • Carryover of culture or process impurities such as Protein A and insulin

Impurity analysis using current ELISA technologies has limitations that include labor-intensive protocols, lower throughput and narrow dynamic range. As a result, repeat analysis is often required, which further delays project decisions and lot approvals. Automating impurity analysis with the miniaturized, microfluidic immunoassays supported by Gyrolab systems shortens turn-around time, broadens dynamic ranges, and delivers reproducible,  high-quality data, with fewer manual operations. These benefits make Gyrolab systems an ideal technology to support all phases of bioprocess and production of biotherapeutics.

Gyrolab immunoassays provide faster time to data compared to traditional ELISA methods

Gyrolab immunoassays provide faster time to data compared to traditional ELISA methods (data courtesy of Medimmune, the global biologics research and development arm of AstraZeneca).

HCP analysis with expanded dynamic range

One primary goal during HCP assay development is a broad dynamic range to avoid repeat analysis and additional sample dilutions. A broad dynamic range is especially important for bioprocess HCP analysis, since the concentration range of HCP impurities in process samples may vary greatly. Gyrolab assays and kits offer broad analytical ranges, reducing the the number of dilutions required to hit the analytical range, thereby reducing the need for repeat runs. Gyrolab CHO-HCP E3G Kit, (broad dynamic range of ~3 ng/mL – 8000 ng/mL), and Gyrolab CHO-HCP Kit 1 are both based on detection antibodies from Cygnus Technologies.

Gyrolab CHO HCP Kit 1

Gyrolab CHO-HCP Kit 1 offers shows a broad analytical range of approximately 2 – 8000 ng/mL compared to 1 – 1000 ng/mL for ELISA.

In situations where assays with process-specific reagents are required, Gyrolab Bioaffy™ 1000 HC Assay Toolbox provides the flexibility and automation needed to deliver rapid results.

Protein A and culture impurities

Other bioprocess impurities may carry over from purification columns or culture media. Gyrolab Protein A Kit detects GE Healthcare MabSelect SuRe™ ligands in samples, and carefully tested Gyrolab assay protocols are available for the analysis of Human Transferrin, Insulin, and PLBL2 impurities. The broad analytical range of Gyrolab immunoassays provides several logs of additional working range expansion over ELISA and a lower minimum required dilution (MRD).

protein A

Ready-to-use Gyrolab Protein A Kit covers a broader dynamic range compared to a commercial ELISA kit.

Comparable to ELISA

Gyrolab assays have been shown by many of our customers to be comparable to ELISAs. For example, the correlation of process samples during purification of a therapeutic protein analyzed by both ELISA and Gyrolab immunoassays is shown below.


The correlation of results for samples throughput the purification of a therapeutic protein is shown. The error bars show the lower variability of data from Gyrolab xP workstation.

Accelerate process impurity analysis with Gyrolab immunoassays

table impurity-1


Host-Cell Protein Analysis to Support Downstream Process DevelopmentLearn more about how scientists at Sanofi have successfully implemented Gyrolab immunoassay system as a reliable platform for high-throughput HCP analysis, in combination with a robotic liquid handling system. The results were comparable to their gold-standard ELISA method.

Read the article

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