Bio-Rad ENrich™ High-Resolution Ion Exchange Columns - Manual (Page 13)

ENrich Instruction Manual 9
3.3 Frit Replacement
The top frit may need to be replaced after extensive column use
or if increasing backpressures are noticed. Always try cleaning
the column in the reverse direction (as described in Section 3.1)
before replacing the frit. A frit kit is available which contains a frit
removal tool, 2 O-rings and 2 frits.
Figure 3 shows a column diagram to assist in the replacement of
the top frit.
Fig. 3. Column diagram.
1. Start buffer through the column at a slow flow rate
(0.5 ml/min or less).
2. Remove the lower end tubing and fitting from the column.
Firmly hold the bottom of the column over a sink or
container.
3. Loosen the lock nut turning it clockwise (Figure 4).
Fig. 4. Loosen the lock nut by turning it clockwise.