How to prepare cell culture samples from a bioreactor in order to perform amino acid analysis with an AccQ•Tag or AccQ•Tag Ultra method - WKB276021

Article number: 276021

OBJECTIVE or GOAL

Prepare cell culture samples, taken from a bioprocessor, for amino acid analysis using the AccQ•Tag Ultra or AccQ•Tag methods.

Aliquot 500 µL of cell culture media or supernatant into a centrifuge tube.
Centrifuge at 2000 Xg for 10 minutes to clear cells and other debris.
Remove 100 µL of supernatant from the centrifuge tube and add it to a microfuge tube.
Add 100 µL of internal standard to the microfuge tube.
Vortex the microfuge tube.
Add 200 µL of high-purity acetonitrile to the sample to facilitate protein precipitation.
Vortex the sample.
Centrifuge at 10,000 RMP for five minutes.
Use 10 µL from this microfuge tube as the sample when performing derivatizations.

If proteins are not present in the cell culture, it may be possible to simply perform sample dilution.

Important notes about cell culture dilution for amino acid analysis:

Sample dilution must be optimized to ensure that all amino acids are present in the linear range of the AccQ-Tag or AccQ-Tag Ultra method.
The derivatization reagent must be present in a 4X concentration vs. the total amino acids present in the diluted sample.

It may be worth trying both procedures (9-step procedure) and the dilution procedure to compare results.