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Glutamine can be measured in the Industrial & Biotechnology applications.

Please see examples below.

Industry & Biotechnology

Glutamine is usually measured in the fermentation and culture control applications

Industry & Biotechnology

A simple and rapid enzymatic analysis for L-glutamine in a variety of biological fluids, e.g. for the monitoring and control of culture media and fermentation processes in biotechnology.


i) Ammonia, liberated from L-glutamine by the enzyme glutaminase (GLU), is converted to L-glutamate by a-ketoglutarate in the presence of glutamate dehydrogenase (GLDH) and excess NADH in a brief pre-reaction:

ii) Under the conditions of the assay, the rate of oxidation of excess NADH by peroxidase (POD) is inversely proportional to the total ammonia present:

A sample blank without GLU measures endogenous ammonia and other NADH consuming reactions and the L-glutamine concentration is obtained by difference.

Technical Summary

Samples Aqueous solutions (pH 5 - 7), culture fluid, etc
Sample Volume 25 µl
Analytical Range 0.5 - 20.0 mmol/L
Precision Typical within-run C.V. = 1 - 2 % @ 8 mmol/L
Detection Limit 0.2 mmol/L
Reagent Stability

Shelf-life 9 months unopened when stored at 0 - 5°C. Reconstituted GLDH/NADH/a-ketoglutarate, 7 - 10 days (2 vials) if stored at 0 - 5°C.

Analyser Sensitivity 1 µmol/L (analyser)


Sample opacity or turbidity presents no problem since the sensor system is electrochemical rather than spectrophotometric.


No analysers are currently available for this analyte.

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