Ask the Expert – Measuring IgG Titer: Need for Real-Time Results, Customization and High Comparability to HPLC

Sponsored by: Roche Custom Biotech
Session ends: July 22nd, 2016, 3:00pm MST
Answers by: Dr. Christian Weilke, Ph.D, Roche Custom Biotech


The successful implementation of PAT (process analytical technology) involves analysis and monitoring of key attributes within the bioprocess.   When measuring critical process parameters, such as IgG titer, the need for high quality data AND real-time access are very important.

  • While HPLC is the gold standard, is it accessible at all stages (early cell line development to manufacturing) and at the frequency desired?
  • What is the impact of getting IgG titer in minutes versus days, without preparing and sending samples for HPLC analysis?

Roche Custom Biotech

This session is sponsored by
Roche Custom Biotech

Roche Custom Biotech offers an IgG assay available on the Cedex Bio and Cedex Bio HT Analyzers which provides fast and accurate measurement of human IgG in cell culture and fermentation media and delivers results that are highly comparable to HPLC (see Graph 1). The assay is based on a turbidimetric method using antibodies directed against the common human Fc region. Additionally, the assay calibration can be adapted specifically to the individual IgG molecule, providing optimal accuracy for artificially engineered antibodies with uncommon structures as well. When compared to gold standard methods like HPLC, the data shows close correlation with decreased turnaround times and less need for manual intervention.

Graph 1: Internal Roche Diagnostics Data

Graph 1: Internal Roche Diagnostics Data

The Cedex Bio and Cedex Bio HT Analyzers provide access to 21 assays including Glucose, Lactate, Ammonia, Glutamate, Glutamine, LDH, IgG, Iron, Acetate, Phosphate, Optical Density, etc, and a test menu that has continuously expanded according to the needs of the market. The systems offer on-board dilution, minimal hands-on maintenance, low sample volume requirement and wide measuring ranges. The Cedex Bio Analyzer is appropriate for low to medium sample throughput while the Cedex Bio HT Analyzer is suited for higher throughput holding up to 90 samples at once (with continuous loading), and offering advanced workflow integration capabilities.

Measuring IgG Titer: Need for Real-Time Results, Customization and High Comparability to HPLC

Dr. Christian Weilke, Ph.D., International Product Manager at Roche Custom Biotech, will be answering your questions regarding the IgG assay and the Cedex Bio and Bio HT Analyzers. Christian holds a Ph.D. in chemistry and joined Roche in 1999. Since 2010, he has been working in Custom Biotech holding several different positions, and is currently responsible for the Pharma In-process Control portfolio.


ask the expert

Questions & Answers

If HPLC is the gold standard what are the advantages of the Cedex?

For some of the relevant analytes in bioprocess control (Eg: IgG or amino acids), HPLC enables a very accurate analysis, but requires: · Highly trained and experienced operators · Suitable standard materials from another source · A specialized lab environment (HPLC is not executed at-line near the bioreactors) · Manual sample preparation (filtration, protein precipitation, […]» Read More

Does the IgG need to be purified before analysis?

There is no sample purification or preparation needed. Cell culture samples can be loaded directly into the Cedex Bio or Bio HT analyzer to perform the IgG quantification. A separation from the cells is not required for the IgG measurement, nevertheless, for sample storage the separation is recommended to prevent alteration of the sample composition.» Read More

Can you measure multiple parameters with one sample?

You can measure any combination of the 21 available tests from one sample, with the flexibility to have profiles with specific test combinations or to run a different test combination on each sample. For the majority of possible combinations of less than 10 tests, one small sample volume of 100 µL is sufficient, as most […]» Read More

How does this monitoring impact sterility of the process?

The Cedex Bio and Bio HT Analyzers are standalone systems and therefore do not impact sterility as you can use your standard process to collect samples from your bioreactor in a sterile way. The samples can then be loaded directly onto the Bio or Bio HT Instrument, or if preferred cell free samples can be […]» Read More

How do you customize this assay for different IgG molecules?

The Roche IgG Assay can be adapted to specific human IgG molecule(s) by a product-specific calibration. We provide a protocol where the Roche calibrator can be replaced by a sample of your individual IgG molecule with a known concentration, and the rest of the assay reagents are fully compatible, with no additional materials or hardware […]» Read More