Integrating Peaks Using Integration Events in OpenLab CDS

Answer

This Information Applies To: Agilent OpenLab CDS 

Issue

Outlining the step-by-step instruction on how to integrate peaks using Integration Events in Processing Method. 

Background

Integration locates the peaks in a signal and calculates their size.

There are two ways to integrate peaks in OpenLab CDS:

1. Edit integration events
2. Manually integrate peaks (See the article How to Use Integration Optimizer in OpenLab CDS 2.5 and above)

Data Analysis includes the same integration algorithms that are available in both OpenLab CDS ChemStation Edition and OpenLab CDS EZChrom Edition. The processing method supports all the initial and timed events from ChemStation or EZChrom. In each method, the preferred integrator must be selected.

Requirements

To be able to carry out the procedure as described, the privilege of Processing Method > Edit general parameters is required. Privileges are configured in the Control Panel.
If the project enforces method approval, the method status must be Generic.

For details, see Method approval on the Agilent OpenLab Help and Learning page.

Steps to Follow

1. In the navigation pane, under Methods, select the processing method that needs to be edited. 
2. In the Processing Method window, click General > Properties > Global tab. 
3. Select the required integrator (Figure 1). The corresponding method section with the specific integration events becomes visible.
   

   
   
   Figure 1. Select either ChemStation integrator or EZChrom integrator
   
   

   For more details, see user resources from OpenLab Help and Learning: Integration Events ChemStation Integration Events EZChrom

4. In the Processing Method window, select Integration Events > Standard node. (Figure 2)
   

   
   
   Figure 2. Standard node for Integration Events
   
   

   Users can set the values either specifically for a given signal or globally for all signals. Global integration parameters are used for all signals. In cases of multidetector instruments, choosing signal-specific events can be useful.

   For more details, see Configure signal-specific integration parameters on the Agilent OpenLab Help and Learning page.

5. There are four ways to Add integration events to the parameters table:
   
   1. Right-click in the area next to the parameters table and select Add integration event from the context menu. (Figure 3)
      If the context menu does not open, users might be in Edit Mode in the parameters table. Press [Esc] to exit the Edit Mode.
      

      
      
      Figure 3. Right-click to add Integration events
      
      

   2.  Click [Insert] to insert a new integration event in the parameters table.
   3.  Go to Processing Method ribbon tab and click Add integration event option. If the Processing Method ribbon tab is not open, make sure to select Processing Method window under the Home ribbon tab or click anywhere in the Processing Method workspace. (Figure 4)
      

      
      
      Figure 4. Add Integration Event in Processing Method ribbon tab 
      
      

   4. Graphically add integration event on the chromatogram (Figure 5)
      
      1. Click the setting icon to open Chromatogram Properties and go to Integrator events.
      2. Select the following check boxes:
         1. Show timed events
         2. Show initial events
         3. Edit timed events to edit the events directly in the chromatogram by dragging the start or stop times with the mouse
         4. Show command hints
      3. Click OK to apply any changes and exit this page.
      4. Right click the chromatogram approximately at the retention time where users want to add the event and select the integration event from the Add integration event drop-down menu.
      5. Provide a value for the new integration event, and click  icon to confirm. The integration event is added to the linked method and shown in the chromatogram.
         

         For more details, see Graphically change integration events on the Agilent OpenLab Help and Learning page.

         
         
         Figure 5. Graphically add Integration Event
         
         

6. Choose the type of event, then enter the required time for the event, or provide a value for the event.
   
   • For example, set Integration to Off at 1 min, and with a second parameter, set it to On again at 2.0 min. Integration is then off starting at 1 min, and on again at 2.0 min. In this example shown in Figure 6, Reprocess All is clicked to see the changes in integrated peaks. (Figure 6)
     

     
     
     Figure 6. Click Reprocess All to see changes in Integration Event
     1. Make changes in the integration event, 2. Click Reprocess All, 3. New change in the chromatogram
     
     

7. There are three ways to Delete integration events to the parameter table. First, click one of the dark gray squares to the left of the parameters table to select the entire row.
   1. Right-click in the area next to the parameters table and select Delete integration event from the context menu. (Figure 7)
      

      
      
      Figure 7: Right-click to delete integration events
      
      

   2. Press [Delete] to delete the selected row in the parameters table.
   3. Go to Processing Method ribbon tab and click Delete integration event option. If the Processing Method ribbon tab is not open, make sure to select Processing Method window under Home ribbon tab or click anywhere in the Processing Method workspace. (Figure 8)
      

      
      
      Figure 8. Delete Integration Event in Processing Method ribbon tab
      
      

8. When developing a processing method, users may need to use different timed events in different combinations. Instead of deleting events and adding new events every time, users can simply enable or disable individual events. (Figure 9)
   1. To disable an individual event, clear the check box in the Use column. When users reprocess an injection, this integration event will not be taken into account anymore.
   2. To enable an individual event, select the check box in the Use column again. When users reprocess an injection, this integration event will be taken into account again.
      

      
      
      Figure 9. Select or deselect Use column in Integration Event 
      
      

9. With ChemStation integrator, it is possible to define some Advanced integration parameters. Here, users can define how non-baseline separated peaks are handled. The advanced integration events are provided for all signals.
   
   

   For more details, see Advanced Integration Events, from OpenLab Help and Learning. See the article How to Integrate Merged Peaks in OpenLab CDS (ver. 2.x) from the Agilent Knowledge Portal Explore this article if users want to explore a newly launched feature Integration Optimizer in OpenLab CDS, from OpenLab Help and Learning.

10. Click Reprocess All to apply any changes. 

Caution: If users already have calibrated the method with the previously chosen integrator, recalibrate it. If users change the integrator, all existing calibration curves are removed from the method. Users can still view the calibration curves stored in the result data, but in order to reprocess a sample they must first reprocess their calibration standards with the current integrator. This way the application ensures that the results are always based on the correct integrator.

Learn how to effectively operate your Agilent OpenLab CDS software: HPLC-OLII-1140eV2 - Agilent Infinity LC systems with OpenLab CDS - Integration and viewing results (Ver. 2.6) e-learning course available from Agilent education