BIO RAD Trans-Blot Turbo, Instruction Manual

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Swirls or missing bands; diffuse
transfers Poor contact between the membrane and the gel. Air bubbles (or excess
buffer when using traditional semi-dry consumables) remain between
the membrane and gel. Use the blot roller to ensure that air bubbles or
excess buffer are removed.
Poor contact between the assembled sandwich and the electrodes
(when conventional semi-dry consumables are used). Use extra-thick
filter paper or add additional sheets of thick buffer-wetted filter paper to
improve contact.
The membrane was allowed to dry out. White spots on a nitrocellulose or
PVDF membrane indicate dry areas where protein will not bind.
Power conditions are too high for your particular gel. Adjust voltage and
current conditions.
The gel electrophoresis may be at fault. Artifacts of electrophoresis may
be produced by poor polymerization, inappropriate running conditions,
contaminated buffers, sample overload, etc. Consult your electrophoresis
manual for more details.
When using a single mini transfer pack, the assembled transfer pack may
have been placed at the extreme edge of the cassette bottom. Ensure
that assembled transfer packs are placed near the center of the cassette
base.
When two mini gels are transferred simultaneously on a midi format
stack, ensure the gels are arranged foot-to-foot (low–molecular weight
portions of the gels are towards each other).
NO LOAD DETECTED is displayed
on the Run screen The unit is detecting the presence of a cassette, but current is not
passing between the electrode plates.
Ensure that the blotting assembly is positioned properly and is thick
enough to contact both the anode and cathode plates.
If using a custom buffer, the buffer may have an ion capacity that is
too low or too high for efficient transfer. Check the concentrations of
components in the buffer.
The electrical contacts on the cassette or instrument may be dirty . With
the instrument unplugged , clean the contacts with a cotton swab or
wipe moistened with isopropyl alcohol.
Trans-Blot® Turbo™ Blotting System 19