Conditioned media, filter or centrifuge? - which way is the best way to prep for ELISA (Oct/15/2007 )

Hi all,

If I am planning save my cell culture conditioned media for an ELISA, which way is the best way to prepare it? Should I centrifuge or use a filter to collect the supernatant? Any experience you have had with this would be helpful to me. Also, is it ok to freeze this media at -20oC?

Thanks a lot!

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For ELISA I usually just spin down to make sure I remove all cells. What are you looking for by ELISA? I will recommend -80C for storage although I guess -20C will do for short term. I actually use to just spin down the 24 well plates, and then transfer sups to a new plate that i will freeze at -80C.

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I would recommend doing just a short fast spin, transferring it to a new eppendorf and either store at -20 if you will go for ELISA within 2days or store at -80 for long time periods.

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I am looking for secretion of VEGF in the medium where the cells are attached. Thanks for your response. I think that I will probably have to spin down the supernatant in a separate microfuge tube and then separately collect the cell lysate to quantify the protein content of the cells. (I'll normalize the VEGF concentration against cell number.)

Thanks your advice is helpful.

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Would 2000 rpm for 10 min be considered short and fast for these purposes?

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