How to Use Integration Optimizer in OpenLab CDS 2.5 and Above

Answer

This Information Applies To: Agilent OpenLab CSD 2.5 and above

Issue

The integration optimizer helps find a suitable set of integration events. It allows integration parameters to be tuned via sliders (peak width, slope sensitivity, height reject, peak separation modes, etc.) and the resulting integration to be previewed in real time in the Chromatograms window. This article outlines the step-by-step instruction on how to use Integration Optimizer in OpenLab CDS.

Background

There are two ways to integrate peaks in OpenLab CDS:
1. Edit Integration Events
2. Manually Integrate Peaks
The new Integration Optimizer Wizard enables easy deployment of integration settings to the lab.

Requirements

For OpenLab CDS 2.5, Integration Optimizer add-on needs to be installed. You can download Integration Optimizer Plug-In package on SubscribeNet. It is available for customers with active Software Maintenance Agreement (SMA).
- Sign in to your SubscribeNet account. Go to Product List > scroll to OpenLab Software > click OpenLab Add-ons. Click the Integration Optimizer Add-on hyperlink to download. Follow the instruction to install the plug-in.
For OpenLab CDS 2.6 and above, this feature is an integrated component. Before upgrading from OpenLab CDS 2.5 to a later version, the Integration Optimizer add-on needs to be uninstalled.
To be able to carry out the procedure as described, you need the privileges: Data Processing > Use Integration Optimizer, Data Processing > Integration Optimizer: Display peak results, and Processing Method > Edit integration parameters.
Result set must be writable. Locked result sets are marked with a lock symbol .
If the project enforces method approval, the status of the result set method that you want to update must be Generic. For details, see Method approval.

Steps to Follow

Load data from result sets or single samples. See Load or add data. Make sure it has a processing method linked.
Select the injection of interest. It's recommended to use a low level of calibration.
Go to Home, expand Layouts, select Integration Optimizer (Figure 1).

Figure 1. Integration Optimizer Layout
1. Home, 2. Expand Layouts, 3. Integration Optimizer
Characterize Chromatogram – Check Use parameters from method to tune an existing method (only available in OpenLab CDS 2.7 and later) or Select integrator. You can choose the integrator of interest from the drop-down menu to start from scratch (Figure 2).
For more details, see ChemStation integrator and EZChrom integrator.

Figure 2. Select Integration: ChemStation or EZChrom
Characterize Chromatogram – Use scroll bar to select the preferred signal if there are multiple signals (Figure 3).

Figure 3. Select preferred signals (if applicable)
Characterize Chromatogram – Integration Start/End: specify the integration range of interest
1. In the Chromatograms window, drag the red Integration Range box to adjust the entire range, or drag the single red lines to adjust the integration start and end time. The integration start and end time will be populated.
2. Alternatively, enter the start or end time manually in the input fields, or remove only one of the two values to leave this end open. To set the integration range back to default, remove both values, or right-click the chromatogram and select Reset ranges.
  The Integration Optimizer will create integration events (Integration ON and Integration OFF) based on these values. No integration event is created for an empty field. (Figure 4)
  
  Figure 4. Integration Start and End
Characterize Chromatogram – Smallest Peak Start/ End: specify the start and end time of the smallest peak that you want to integrate
1. In the Chromatograms window, right-click the smallest peak, and select Move smallest peak range here.
2. Alternatively, drag the green Smallest Peak Range box to adjust the entire range, or drag the single green lines to adjust the smallest peak range start and end time. The smallest peak start and end time will be populated (Figure 5).
3. To set the smallest peak range back to default, remove both values, or right-click the chromatogram and select Reset ranges.
4. See Hints for choosing the smallest peak range.
  
  Figure 5. Smallest Peak Start and End
Click Next to proceed to continue with the process.
Integration & Tuning:
1. For ChemStation integrator, use slider to adjust Peak width, Slop sensitivity, Height reject, and Skim ratio. Then, select among four options for Peak separation mode to integrate peaks that do not show baseline separation:
  - Valley dropline,
  - Baseline at valleys,
  - Exponential skim, or
  - Straight skim.
    For Exponential skim and Straight skim, you can also tune the skim ratio. For ChemStation integrator, the peak separation mode will apply to all signals in the method. (Figure 6)
    
    Figure 6. Integration Tuning - ChemStation integrator
2. For EZChrom integrator, use slider to adjust Width, Threshold, and Minimum area. Then, select between two options for Peak separation mode to integrate peaks that do not show baseline separation:
  - Valley dropline, or
  - Valley to valley. (Figure 7)
    
    Figure 7. Integration & Tuning: EZChrom integrator
3. The value ranges of the sliders are set automatically based on the selected injection, or based on an existing processing method.
4. For more details, see Tune the signal.
To compare different combinations of integration parameters, create snapshots. This feature is only available in OpenLab CDS 2.7 and later. Click the “+” icon to store the current set of integration parameters as a Snapshot. You can create up to nine snapshots.
Automatic integration will be performed with the selected snapshot.
Snapshots are signal-specific, cannot be overlaid, and they are stored in memory. They get cleared when restarting Wizard and they are not saved with method.
For more details, see Compare integration parameters.
The integration parameters shown in this step always apply to the signal that you focused in Characterize Chromatogram step. It does not matter if you selected other signals or changed the focused signal in Integration & Tuning step or Finalize Parameter step.
If necessary, modify the values manually in the integration events table:

a. In the Standard node: Add, delete, enable, disable, or modify timed integration events.
b. In the Advanced (All) node: Modify the available integration events.

Each modification is immediately reflected in the Chromatograms window.
To continue tuning the integration parameters using the sliders, click the Previous button, or click Integration & Tuning in the upper navigation bar.
To review the initial settings in a read-only mode, click Characterize Chromatogram in the upper navigation bar.
If the integration result looks good, click Update Method to transfer the parameters to the link method. This button is inactive if no method is linked.
These 2 options are available in OpenLab 2.7 and later:

a. Update Method (signal specific)
b. Update Method – Global (global settings)

After updating the method, the Integration Optimizer jumps back to Characterize Chromatogram step. This allows you to work on another signal if needed. The integrator, integration range and smallest peak range are still the same.
To restart the Integration Optimizer with default parameters, click Restart Wizard. (Figure 8)

Figure 8. Finalize Parameters
After finishing using the Integration Optimizer feature, click Method layout view to go back to the processing method window (Figure 9).

Figure 9. Exit Integration Optimizer layout
1. Integration optimizer layout, 2. Method layout