detection of protein (20-30kd) by western

Nicole Rapior cbiei01 at
Fri Feb 13 21:22:41 EST 1998

Didier Fesquet wrote:
> hi, I am having trouble to detect protein in the range of 20-30 kd by
> western blotting. I am tranferring the gel onto Nitrocellulose(0.22um)
> as well as immobilon P using semi dry tranfer (biorad apparratus) and
> the recommended voltage 10volt , 30min for a mini gel. upon transfer, by
> ponceau staining , I could not detect sharply stained protein band. what
> happen!
> any help is wellcome
> thanks
> didier

Hello Didier,

with your small proteins it is possible that they just pass through your
nitrocellulose membrane. To prevent this use a double layer of
nitrocellulose and adapt your blotting conditions. We keep the current
constant depending on the size of the gel (5 mA/cm2). You also might
stop the blotting already after 20 minutes to prevent the proteins
passing through the membrane.

Good luck!!!!

Nicole Rapior
Physiol. Chem. Institut
Hoppe-Seyler-Str. 4
D-72076 Tübingen

phone: 07071-297-3353
fax:   07071-29-3361
email: cbiei01 at

More information about the Methods mailing list