Bio-Rad AG® MP-1M Anion Exchange Resins - Manual (Page 11)

tions 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 sample.
7. The actual flow rate that is used will depend upon
the application, the resin, and the column cross-sec-
tion. To obtain flow rates for any given size column,
multiply the suggested flow rates in Table 6 by the
column cross-sectional area. Table 6 gives typical
flow rates of analytical grade resins.
8. If an anion free solution is the goal, collect the efflu-
ent. If the concentrated anions are of interest, allow
all of the sample to pass through the column, then
elute the anions off the resin with a solution contain-
ing a counterion of higher selectivity than the bound
anion.
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exchanged onto the column. For unknown solutions,
use deionized water.
4. Slurry and pour the resin into the column.
Equilibrate the resin in the initial buffer using 3 bed
volumes of buffer. Poorly equilibrated resin will not
give reproducible results. Alternatively, equilibra-
tion 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 the starting buffer through the
column.
5. Slurry the resin in the initial buffer and pour the col-
umn. Allow excess buffer to pass through the col-
umn, leaving enough buffer to just 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 por-
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