Packing Eichrom
2 mL Columns$1--
6XPPDU\ Eichrom offers empty 2 mL columns and bulk resin for customers who wish to pack their own columns.
This application note will offer advice on slurry packing columns that will exhibit favorable flow conditions and efficient
separations. Some hydrophobic, difficult to wet resins may require additional treatment prior to slurry packing or may be
dry packed.
AC-120AC-103AC-130Eichrom snap tip 2 mL Columns (AC-141-AL)
come with the bottom frit inserted. Top frits
and column top caps are also included.

2 mL Column Racks (AC-103), Column Tip Closures (AC-130),
and 2-piece 25 mL Extension Funnels (AC-120) are also available.

The first step in slurry packing columns is to wet the resin by mixing with an appropriate aqueous phase. For mostEichrom resins, a solution of 0.05M HNO3 is ideal for column packing. Add a volume of resin sufficient to pack yourcolumns to 3-5x that volume of 0.05M HNO3. Mix the resin by vortexing, swirling or gently tumbling. Avoid vigorousshaking, which can lead to air bubbles that can degrade column flow and separation efficiency. If a portion of the resin
floats on the surface of the 0.05M HNO3, centrifuge the sample. Repeat mixing and centrifuging as necessary to achieve awell wetted resin with minimal amount of floating material.
Some more hydrophobic resins will not wet well in 0.05M HNO3. Table 1 lists some difficult to wet resins andalternative matrices to facilitate wetting. The resins in Table 1 can be wetted by replacing the 0.05M HNO3 with thealternative slurry matrix and following the steps above. Once DGA, LN2 and LN3 have been wetted with the alternativeslurry matrix, centrifuge and decant the aqueous phase and replace with 0.05M HNO3 for storage and column packing.
Table 1. Slurry Matrices for Difficult to Wet Resins
Resin
Slurry Matrix
Prefilter
0.05M HNO3
Ni Resin
0.15M Ammonium Citrate
DGA, Normal
2M HNO3
DGA, Branched
2M HNO3
Cu Resin*
0.05 - 2M HCl
LN2
1M HNO3LN3
2M HNO3*Cu Resin will float on the surface of the solution
even when wetted.

Wettedresin,ideal forslurrypackingcolumns.

Floatingor poorly
wettedresin,difficult toslurry
pack intocolumns.

The packing method is written assuming a 0.05M HNO3 slurry matrix. For Ni Resin and Cu Resin, replace 0.05M HNO3with the appropriate alternative. Pre-packed Eichrom 2 mL columns contain 1.6 mL of resin. This method was written toreplicate this fill volume.
As the resin is wetting in the appropriate matrix, addempty 2 mL columns to a column rack or other support.
Add a small volume of 0.05M HNO3 to soak the bottom
frit and remove air bubbles. Soak until no can be seen
escaping from the frits.

Full 2 mL columns should have a bed height of 4.1 + 0.2
cm. Add additional slurry to meet this height or remove
excess resin using a plastic transfer pipet. Leave enough
0.05M HNO3 above the packed bed to fill the column anda portion of the reservoir.
Place a pre-soaked frit into each column. Using a glassor plastic stir rod, push the frit to the top of the packed
bed. Decant the 0.05M HNO3 above the top frit and rinseaway any residual resin from above the top frit using
0.05M HNO3.

Add enough top frits for eachcolumn to a centrifuge tube
with a small volume of 0.05MHNO3. Soak the frits toremove air bubbles. Swirl orvortex to mix, but avoid
vigorous shaking.

Decant the 0.05M HNO3 from the empty columns. Mix theslurry of resin and 0.05M HNO3 to suspend the resin. Add
the resin slurry to each column until the reservoir above
the column is ~half full. Allow the resin to settle (~1 hr).

If storing the columns for future use, fill the reservoir
above the top frit ~half full with 0.05M HNO3 and place a
top cap on each column. If using the column immediately,
snap off the bottom tip, allow any excess 0.05M HNO3 todrain, and begin the column preconditioning step.
'U\ 3DFNLQJ &ROXPQV Some difficult to wet
resins can also be dry-packed into columns:
1) Place 2 mL columns with bottom frits in column rack.
2) Weigh 0.65 + 0.05 g of dry resin into each column.
3) Tap to settle the resin.
4) Place a top frit on each column and push the frit tothe top of the resin bed.
5) Rinse away any excess resin above the top frit.
6) Add preconditioning solution to the column reservoir.
Over pressure or vacuum may be required to initiate
column flow.
7) Allow solution to drain through column.

1955 University Lane Lisle, IL 60532, USA+1 (630)963-0320

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