Why do we use sponges in the Western Transfer? - (Aug/16/2012 )

Hi!
Just as a curiosity!

Why do we use sponges in Western Blot transfer?

Thanks!

Have a nice day!

-Raquelina-

haha, interesting question
I guess to keep your membrane and a gel squeezed together, without it those two wouldn't be tight enough.

-bithorax-

BIthorax is correct.

-bob1-

for semi-dry blotting, to have a stock of transfer buffer; after more than 2h semi-dry blotting, buffer is usually vaporized, without sponges, blotting time should be shorter;

another function is to spread the pressure on the gel more equally...

-Inmost sun-

Thank you all!
More or less was what we were thinking of. We also checked the paper where first Western was made and they used Scotch Brite sponges! Sadly, they didn't explain why.

Have a nice day!

-Raquelina-

Cheap, easily obtainable, and easy to clean/rinse out - also more permeable to the buffer so you don't get a region where the electrolytes run out during transfer.

-bob1-