Introduction
Preparing Reagents, Standards and Samples
Reagents:
Dosino Reservoir:
18 mega-ohm DI water
Suppressor Rinse Solution:
0.1% methanol in DI water (1 mL methanol to 1 L DI water)
Suppressor Regenerant Solution:
0.05 M sulfuric acid solution (2.7 mL sulfuric acid to 1 L DI water)
Anions Eluent:
3.2 mM sodium carbonate/1.0 mM sodium bicarbonate solution (purchase concentrated packs from Metrohm, called “A Supp 5 Eluent Snips”)
- snip off tube with scissors and pour contents into a 1 L volumetric flask
- rinse the tube with DI water, adding to the flask
- bring flask to volume
Cations Eluent:
1.7 mM nitric acid/1.7 mM PDCA (pyridine-2,6-dicarboxylic acid)
- dissolve 0.248 g PDCA in DI water in a 1 L flask
- add 106 µL concentrated trace metals grade nitric acid
- bring flask to volume with DI water.
To make a carboy’s worth:
- in a 2 L volumetric flask, mix 872 µL nitric acid, 2.272 g PDCA with DI water and bring to volume.
- This may involve using a stir plate with a stir bar in the flask. Pour into the carboy.
- Add three more 2 L flasks filled with DI water.
Instrument Operation
Startup
- Load a method (sets instrument’s operational parameters).
- Select METHOD icon in left panel.
- Select File -> Open -> select the method.
- You can then save the method with a new name for the current Expedition (File -> Save As).
2. Make a new database for the Expedition (saves results in a central Expedition database)
- Select DATABASE icon in the left panel.
- Select File -> Database Manager.
- Select Edit pulldown then New.
- Type in a new name.
- Here you can also make a database backup.
- Select Database Manager again and Backup, giving a unique Expedition name.
- Go back to the METHOD panel.
- In the Evaluation window, click on Results icon.
- Select the Database tab.
- Double-click on the Name Database field and select your database name for the Expedition.
3. Go back to the WORKPLACE icon in the left panel.
- Select the method that you want the instrument parameters to be set at (Equilibrium tab).
4. Confirm all reagent reservoirs are filled, peristaltic pump tubes are in good shape and their platens are engaged.
5. To start the instrument, select Equilibration tab > Start HW button.
- To shut down the instrument, select the Stop HW button.
Monitor instrument conditions (Watch window) for ~ 60 min before starting a sequence.
The anions baseline should be ~ 1 µS/cm. Suppressor may cause a small peak every 10 min or so. The anion pump pressure should be around 6.5 – 7.0 MPa.
The cations baseline should be ~ 870 µS/cm. The cation pump pressure should be around 4 – 4.5 Mpa.
The column thermostat display appears red until reaching 45°C. Allow the columns to come to temperature before starting sequence.