GE Typhoon 9200 Operating Instructions Manual page 33

4 Operation
4.3 Preparations before start
Table 4-1. Material recommendations for low-fluorescent sample handling.
Material
Gels, general
Agarose gels
Polyacrylamide
gels
Solvents
Membranes
Transparency
support
Chemiluminescent sample handling recommendations
•
•
32
Recommendation
Background fluorescence contributed by the gel matrix
increases with gel thickness. Always use the thinnest gel
practical for your experiment, especially for agarose gels.
Make sure your glass plates are absolutely clean before you
pour the gel. Grease and fingerprint oils from the plates can
stick to the gel surface and attract dust and fluorescent dyes.
Make sure the agarose is completely dissolved and well-mixed
before pouring your gel. Also, avoid generating bubbles when
mixing and pouring. Uneven agarose concentration and
bubbles affect light scatter and can cause artifacts and
interfere with quantitation.
Polyacrylamide gels are usually clear and thin (less than 1
mm). The background contribution from the gel material is
generally very low.
Spectroscopic-grade solvents have the lowest
autofluorescence.
You should scan a test piece of each type of membrane you
plan to use and check that the background is low enough for
your purposes.
To avoid contaminating the glass platen and sample lid, you
can place a sample, such as a membrane, between two pieces
of transparency material. For detailed instructions, see the
Typhoon User´s Guide.
Follow the manufacturer's guidelines for preparing membranes or microplates for
chemiluminescence scanning.
To avoid compromising the chemistry on the membrane, place the membrane
between two pieces of transparency material or between sheet protectors.
Alternatively, place the membrane in a plastic bag to keep the sample wet and
surrounded by substrate.
Typhoon Operating Instructions 28-9623-56 AA