Is it possible to freeze cell culture supernatants and store them before analyzing NO production by Griess reaction?

01 November 2018 1 6K Report

I need to measure NO production by in vitro generated mouse MDSCs. Since I cannot store diluted Griess reagents for a long time, I want to collect supernatants and then analyze them all together. Is it possible to store supernatants at -20C for a couple of months before the analysis? Do I need to filter supernatants before analyzing to remove proteins or it is enough to centrifuge them?

Also, I am going to use DMEM medium, since it contains less nitrtates as compared ro RPMI-1640. Will phenol red in the medium interfere with the nitrite absorbanse at 540?

Josselin Nespoux

Hello Yuliya Perfilyeva ; did you try to measure nitrites after storing supernatants in the freezer? How did the results look like? Does freeze/thaw affect nitrites concentrations?

Thanks

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