RestekCapillaryColumn InstallationGuide
Press-Tight® connectors
Vu-Union® connectors
(vacuum/high pressure &
capillary/microbore)
ConnectingColumnswithPress-Tight®Connectors
1. Cut the column ends squarely.
2. Wipe the column ends withmethanol to lubricate and clean.
3. Carefully insert the ends into the Press-Tight® Connector.
4. Visually inspect (see photo).
5. Leak-check using a thermal conductivity leak detector.
E. ConnectingStainless Steel Tubing
In order to connect MXT® columns, special connectorsmust be used. TheMXT® Low
Dead Volume connector (cat.# 20397, 20394) andMXT® LowDead Volume "Y"
connector (cat.# 20396, 20395) are Silcosteel®-treated and deactivated tomake them
inert to active compounds. Theywill not cause peak tailing or affect system inertness and
can be used up to 400°Cwithout degrading the deactivation layer. Stainless steel
replacement ferrules are available to fit 0.28mm IDMXT columns (cat. # 20398) and
0.53mm IDMXT columns (cat. # 20399).
MXT® tubing can be connected to fused silica tubing by using a capillary Vu-Union®
connector (cat.# 20418) provided the end of theMXT® column is properly burnished into
a conical shape. The flat side of a ceramic scoringwafer can be used to polish or round
the column end into a conical taper. AnMXT® connector with a special ferrule (cat. #
20259) can also be usedwith a fused silica column. A fused silica Press-Tight® connector
cannot be usedwithMXT® columns becausewithout polyimide coating on the outside of
the tubing, a leak-free connection cannot be obtained.
F. ColumnMaintenance andRinsing
Maintenance is necessary if a column experiences high bleed (that cannot be decreased by
overnight conditioning), adsorption of active components, peak tailing, or changes in
relative retention times. Cutting two loops (approximately onemeter) from the column
inlet is often sufficient to restore a contaminated column. However, highmolecular weight
residue carried deep into the column bore can only be removed by solvent rinsing. To
remove pyrolyzed contaminants that are not solvent-soluble, cut two loops from the
column's inlet and one loop from the outlet. Closely examine the inlet end of the column to
make sure that all contaminated tubing has been removed. Occasionally, it becomes
necessary to removemore than two loops from a heavily contaminated column to restore
it to acceptable performance. Solvent rinsing removes only soluble contaminants andmay
not always restore a bonded phase capillary column to its original performance.
FigureM
illustrates the performance of a column that has been successfully solvent-rinsed. Choose
a series of polar and non-polar volatile solvents that will solubilize the suspected
contamination. Only use solvents shown in
TableVII
to rinse Restek columns. If you are
