Bio-Rad Bio-Rex® 5 Anion Exchange Resins User Manual
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section. Table 4 gives typical flow rates of analytical
grade resins.
8.
If an anion free solution is the goal, collect the
effluent. If the concentrated anions are of interest,
allow all of the sample to pass through the column.
Then, elute the anions from the resin with a solution
containing a counterion of higher selectivity than the
bound anion.
Table 4. Suggested Flow Rates for Ion Exchange Resin
Columns
Application
Flow Rate
ml/ min/ cm
2
Removing trace ions
5-10
Separations with very few components
1-3
Separations of multi-component samples
0.3-1.0
Using high resolution resins with small particle size
0.1-0.2
Sample Protocol
Separating Neutral Sugars and Acids from Wine
and Grape Must Samples
This procedure describes a method for separating
organic acids and neutral sugars using Bio-Rex 5 resin,
according to the protocol described by McCord,
et al.
1
11
Alternatively, equilibration can be done by the batch
technique, prior to pouring the column. First, convert the
resin to the appropriate form, then suspend it in the
starting buffer. Check the pH with a pH meter while
stirring continuously. Adjust the pH by adding acid or
base dropwise to the buffer until the desired pH is
obtained. Then transfer the resin to the column and pass
1 bed volume of starting buffer through the column.
5.
Slurry the resin in the initial buffer and pour the
column. Allow excess buffer to pass through the
column, leaving just enough buffer to cover the top
of the resin bed.
6.
Apply the sample dropwise to the top of the column
without disturbing the resin bed. Drain the sample
into the top of the bed and apply several small
portions of starting eluant, being very careful to rinse
down the sides of the column and to avoid stirring up
the bed. Drain each portion to the level of the resin
bed before the next portion is added. Never allow the
liquid level to drain below the top of the resin bed.
7.
The actual flow rate that is used will depend upon
the application, the resin, and the column cross
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