Protocol Online logo
Top : Forum Archives: : Immunology and Histology

ELISA - new kit without coating buffer - (Mar/26/2007 )

I just got a new ELISA kit from DuoSet (R&D Systems).
The first step is to coat the plate with antibodies overnight, but there is no coating buffer, the protocol says
to use only PBS...
Does anyone have an idea of how the antibody manages to adhere to the plate under these conditions?


If they say that using PBS is fine, then they have tested this and it works for them. If you feel more comfortable using something else, then you could use a pH 9-9.5 50mM Bicarbonate buffer. They were most likely just trying to make the protocol easiest on the end user.


some antibodies prefer an alkaline pH (carbonate buffer) some prefer neutral (PBS) some even prefer something acidic (citrate)
If R and D says to use PBS, it means they tested it and it works so.
I used several kits from R and D, and it always worked. Don't change their protocol.


I have accidentally coated the ELISA plate with PBS, instead of Bicarbonate buffer pH 9.5. The assay was still fine but not as good as bicarbonate buffer.

-Minnie Mouse-