Bio-Rad Bio-Gel P Polyacrylamide Gel - Manual (Page 10)

and myoglobin are visible and can be seen as they migrate through the
column.
Section 6
Sanitation and Sterilization
Bio-Gel P gel can be sterilized within a column by using 3%
hydrogen peroxide in water, ethanol solutions (the gel will shrink
slightly in alcohol), diethyl pyrocarbonate, or thimerosal 1:10,000.
Hydrated Bio-Gel P gel can be autoclaved at pH 5.5-6.5, at 120 °C,
for 30 minutes. When autoclaving, the gel may swell 4-25 times the
original volume. Swelling increases with increased pore size.
Section 7
Storage
Packed columns of Bio-Gel P gel can be stored indefinitely if
maintained at neutral pH in the presence of a bacteriostat such as
0.02% sodium azide. Packed columns should be stored at 4 °C.
15
Section 5
Void Volume Determination
and Calibration
The void volume (V
o
) of the bed is equal to the elution volume (V
e
)
of excluded material. The void volume of the bed should be determined
and the bed should be tested for uniformity of eluant flow before
applying experimental sample. Colored proteins such as hemoglobin
or ferritin are convenient for this procedure. Blue dextran is not
recommended for V
o
determination because it is heterogeneous and
may give variable results. It also may bind nonspecifically to the gel.
Using standard protein allows verification of the column pack-
ing and protein elution. It also allows comparison of different columns,
and different packing material, without wasting precious sample.
Bio-Rad's Gel Filtration Standard is a mixture of five proteins with
known relative molecular weights; thyroglobulin (M
r
670,000), bovine
gamma globulin (M
r
158,000), chicken ovalbumin (M
r
44,000), equine
myoglobin (M
r
17,000), and vitamin B
12
(M
r
1,350). Vitamin B
12
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