Michael Witty <mw132 at mole.bio.cam.ac.uk> wrote:
:On Sat, 23 Jun 2001, Dima Klenchin wrote:
::> Michael Witty <mw132 at mole.bio.cam.ac.uk> wrote:
:> :> >Another aspect that they repeatidly point to is the possiblity of a short
: by
:> :> >using nitrocelluse or stack paper that is larger than the gel itself. The
:> :> >make a big deal about having these exaclty the same size as the gel.
:> :> >
:> :>
:> :> You must be joking (or they are).
:> :
:> :To support poor old Maniatis: I can see how it is _possible_ to make a
:> :short circuit that way. But difficult once a person is experienced in the
:> :method. Mike.
:>:> How? I do not see it possible in wet transfer. Dima
:>::Dima,
: here is how it might happen if the stack of paper towels makes good
:contact with the buffer reservoir rather than just touching the gel. You
:have to position the papers towels _really_ badly. Mike.
:: ---------------------------------
: -- > --------------------------- Badly positioned stack of gels
: - / -----------------------------
: I IIIIIIIIIIIIIIIIIIIIIIIIII Gel
: I B U F F E R
:Path of
:short
:circuit
^ ^ ^
| | |
Here here and here
(no gel or towels)
current will be the same.
As far as I can imagine, conductivity of buffer and towels
and porous gel wetted in that buffer are essentially equal.
In this case, you'd have to have that "badly positioned stack
of towels" to be of enormous thickness or insert an insulator
between gel and paper (air bubble, for example) to have
the current bypass the gel.
- Dima
