Method for the analysis of anions using the Dionex DX500

Start up and run

1.       Start up computer if not already on. Check the paper supply in the printer.

2.       Check level of eluent. For an overnight run of about 60 samples the level should be around 1600 ml. - If low prepare more.

3.      Turn on Helium gas at the top of the tank. Do not adjust the line pressure.

4.      Open Peaknet main menu.  It is located in the start menu under “Programs/Dionex Programs”.

5.      Degas the eluent. To do this place the plastic tubing in the helium outlet on the bottom of the cap and place tube in the eluent.  lightly screw on the cap a few turns.  Make sure the cap is not sealed tight for the degassing procedure.  Check to see if there is a Wipe-All in the tray beneath the bottle to contain any spill.  Degass for about 5 to ten minutes.  When finished remove the plastic tubing that was installed and replace cap, sealing it this time.

6.      If new eluent was added prime the pump.  This is done by first loading a method to start the pump.  To load a method, open the RUN window in the Peaknet program.  Under “file” on the menu bar select “load method”.  Select the method you wish to run.  In most instances it will be “anions.”  This will start the pump.   Under “run” on the menu bar select direct control of the GP50.  Highlight the low pressure limit and change to “0.”  Next  open the bottom door to the GP50 and locate the pressure transducer valve.(top center on the pump.)  Turn this valve one or two turns counter clockwise.  On the direct control screen press the prime button.   This will start the pump priming.  let it continue until all air is expelled from the tubing.  Check the sample waste line for a reference.  This should only take about one or two minutes.  When it clear, press the prime button again to stop the priming process.  close the pressure transducer valve.  In the direct control screen re-enter the low pressure limit for the pump(1000). 

7.      If not already loaded, load the method you plan to use for the day.  this is done by first entering the RUN screen from the peaknet main menu.  under “File” select “load method” Load the “anions” method. 

8.      With the method loaded, we must establish a base line to determine stability.  Under the “run” menu select “baseline”. 

9.      Prepare a schedual for today’s run. Important, create a new schedual for each run do not modify and old schedual.  Enter the SCHEDUAL  editor from the peaknet main menu.  Under “file” select “new schedual”.  Type in the standard and sample ID’s.  Identify the entry as sample, calibration standard or check standard.  Identify the level of each of the Calibration and Check Standards.  Double click on the box to enter the method.  select a method for the first entry.  Use the fill button located on the menu bar to aply that method to the rest of the samples.  Enter a datafile name for the first entry (Use the date for easy reference) and fill the rest using the fill button, just as with the method.  At the end of the schedual enter an ID called shutdown.  Identify the shutdown method for this entry.  Enter a file name to avoid a error message when saving the schedual.  Save the completed schedual using the date as the file name. this will aid in the future reference of data files.

10.  Load the auto sampler with the samples.  The black dots on the shuttles should go tho the right.  The caps should be aproximately flush with the top of the vial.  To advance to the first sample press the hold button on the front of the autosampler and it will advance to the sample.

11.  In the RUN screen from the Peaknet main menu, under “file” select “Load Schedual”.  Under the “run” menu select “Start”.  To avoid complications in the processing of the final data be sure that the Schedual is completed and saved in it’s final form before starting the run. Tell the machine to run a batch file at the end of the run.  Identify the file to be named the date of the run.

Shutdown Procedure

1.       After the last sample is finished, check to see if a shutdown method was run.  If so the supressor column and the pump will be off.  If not enter the RUN screen from the Peaknet main menu.  Under “file” select “Load method”.  Load the “Shutdown” method.

2.      To see if the supressor is off view the SRS reading on the main screen of the ED40.  On the GP50 the ON/OFF button will higlight  off when it is not running.

3.      Turn off the gas at the top of the tank.  Do not adjust the line pressure.

4.      If a batch process was not run at the end of the schedual, perform a batch process on the data.

5.      Flush out the back of the pistons.

6.      If leaving over the weekend Shutdown the computer.  This is done from the start menu.  It may also be wise to turn off the DX500.