PSS Polymer Standards
Service GmbH
In der Dalheimer Wiese 5
55120 Mainz
|
Germany
Polymer Standards
Service-USA, Inc.
160 Old Farm Rd, Suite A
Amherst | MA 01002 | USA
Phone
+49 6131 96239-0
Fax
+49 6131 96239-11
Web
www.pss-polymer.com
Phone
+1 413 835-0265
Fax
+1 413 835-0354
Web
www.pss-polymer.com
Tip: When using PSS MCX columns with laser light scattering detectors, it is recommended that
they be purchased pre-equilibrated for light scattering (Lux version, precolumn P/N 299-2200,
analytical P/N 299-2201). Extra steps must be undertaken to obtain optimum low noise baselines.
Filtering solvents under vacuum through a 0.2µm filter and avoiding the use of salts and other
additives in the eluent can improve performance
.
Noting the direction of flow etched on the column, connect the inlet fitting with the injector or preceding
column using the appropriate nuts and new ferrules at each end of the tubing. Ensure that the capillary
is as far as possible into the injector or column head before tighten the nut. Do not overtighten. The
nut should be tightened enough so that the ferrule bites into the capillary tubing and no leak occurs.
Excess force should not be required.
To prevent trapped air being pumped into the column, unscrew the nut at the column inlet and slowly
pump a few drops of eluent to waste before reconnecting the column.
2.7 Connecting Columns in Series
For connections between columns use the column connector delivered with each PSS MCX column.
The precolumn should be connected to the injector and the remaining pore sizes connected in
sequence of increasing pore size so that the largest porosity is closest to the detector. Each time a
column is added, follow the procedure 2.6 above.
2.8 Connecting the Column to the Detector
Connect the outlet fitting of the column to a long piece of 1/16” tubing to take the eluent to the waste.
Pump 3-4 column volumes of eluent through the column to waste at the recommended operational
flow rate. Check for any leaks. Stop the flow, remove the waste tubing from the outlet and connect to
the detector using the appropriate nuts and new ferrules at each end of the tubing. Apply the desired
flow rate, again checking for leaks. As soon as the detector has stabilized, the column is ready for use.
2.9 Testing Column Performance
To verify correct installation, the column can tested by measuring the plate count/meter and the
resolution to compared with the CoA noting that the measurements are a reflection of the dispersion in
the whole system and not just the column alone. See the
Full User’s Guide
for details. Also note the
back pressure in the chosen eluent. These parameters can be used to monitor ongoing column
performance and to diagnose problems.
3. Usage Guidelines
3.1 Eluent Preparation
Use high quality HPLC grade eluents, free from large particles filtered using a 0.45µm filter if required.
De-gas the eluent thoroughly, preferably using an online degasser.
3.2 Transferring to different solvents
Only use PSS MCX columns with compatible eluents.
Prepare the GPC/SEC system with the new eluent. Connect the column/column set to the injector and
attach some 1/16” tubing to the outlet directed to waste. Pump approx. two column volumes of the
eluent at a tenth the optimum flow rate through the column(s) and then slowly increase the flow rate to
half the optimum flow rate and pump a further eight column volumes e.g. for 300mm x 8.0mm
columns, start at 0.1mls/min and increase to 0.5mls/min. Stop flow and connect the column(s) to the
detector. Start flow and increase the flow rate step by step up to the desired value. Ensure that all
detector lines are completely purged and that the system is thoroughly equilibrated before making
measurements.
