Question

Why should bubbles be avoided in a western blot?

Answer 1

to allow for a proper transfer of the protein to the western blot membrane

Explanation:

once the SDS-PAGE is done the gel is removed from the cast and then western blot setup is made as shown in the figure, once the setup is done electric charge is applied with protein gel on the negative side and membrane on the positive side. once this setup is complete then proteins are transferred on to membrane due to electric field applied.

as there is a constant electric field applied, if the bubbles creep in between gel and membrane then the protein will not be able to transferred to the membrane because of following reason

1. there is a gap in between the membrane and gel where there is a bubble, it will not be able to maintain a electric field as electric field inside a hollow sphere is zero which here is our air bubble.

as electric field is required for transfer of proteins to membrane but due to air bubble no electric field is not present thus no protein transfer

All you people are welcome to update the answer
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