How long can I leave the coating antibody on? - (Nov/22/2008 )

Our protocol for coating a plate for an ELISA (tnf-a) says to leave it in the fridge overnight - does anyone know if its ok to leave it more than one night? Upto 48 hours?

I think so, I've once incubated for over 60 hours and had no problem. I suspect that if there is no contamination it can last much longer and at a pH 9.6 it will be less a problem than at a pH 7.4

I have tried one week...no problem.

In the frig you can leave a long time...just make sure you seal your plates/wells. You can also coat at RT for 1-2 hours; block; and store dry sealed in plastic bag with dririte pouch.

YOu can store the plate for longer time also , only thing you have to make sure that the buffer should not be effected with contamination like growth . Mostly PBS buffer is growth prone . if your plates are sealed and stored properly you can use it after.


correct me if iam wrong

regards
sudhakar mutyala

As a rule of thumb you can't really over-incubate any of the steps in an ELISA except the one where you add substrate (assuming a colorimetric ELISA). Though you should always try to be consistent, and of course microbial growth becomes an issue if you take it to the extreme...