Bio-Rad Mini Trans-Blot® Cell - Manual (Page 18)

12 Mini-Trans-Blot Electrophoretic Transfer Cell
The gel holders may warp, and the transfer buffer may boil
and evaporate (further increasing conductivity). This would
result in a potential safety hazard. Refer to the PowerPac
Basic power supply instruction manual for setting current
limits and run times. The Mini Trans-Blot cell is also
compatible with the PowerPac HC power supply.
Use of a stir bar during transfer
For all blotting applications a stir bar must be placed
inside the Mini Trans-Blot cell and the entire unit be
placed on a stir bar mixer, so that the transfer buffer
is stirred during the course of the experiment. This will
help to maintain uniform conductivity and temperature
during electrophoretic transfer. Failure to properly control
transfer buffer temperature results in poor transfer of
macromolecules and poses a potential safety hazard.
Transfer buffer pH
Do not adjust the pH of transfer buffers unless specifically
indicated. Adjustments of the transfer buffers pH, when
not indicated, will result in increased buffer conductivity.
This is manifested by a higher than expected initial current
output and a decreased resistance. It is recommended
that the buffer conductivity and resistance be checked
with the PowerPac Basic power supply before starting
each transfer.
Transfer buffer recommendations
Use only high quality, reagent grade methanol.
Contaminated methanol can result in increased
transfer buffer conductivity, as well as poor transfer of
macromolecules. Do not reuse transfer buffers or dilute
transfer buffers below recommended levels. Reuse of
transfer buffers is not advised, since these buffers have
most likely lost their ability to maintain a stable solution
pH during transfer. Dilution of transfer buffers below their
recommended levels is also not advised, since this will
decrease buffering capacity.