MagIC Net Reprocessing: Calibration and Data Evaluation

Introduction

The attached pdf walks you through reprocessing data in MagIC Net. It includes an overview of the database features and step-by-step instructions of how to reprocess data.

Topics included:

• Peak Integration
• Retention Times
• Component Labeling
• Updating Calibration Concentrations
• Calibration Curve and Types
• Evaluating Calibration Curves
• Saving the Calibration to the Method
• Applying Calibration to Samples

Database Features

1. Navigate through pages of database. 
2. Scroll through determination overview table. 
3. Click a line on Determination Overview to see its data. 
4. Results table. 
5. Chromatogram and calibration curves. 

Reprocessing Data

1. Navigate to the Database window of MagIC Net. 
2. Select a series of calibration standards that have been previously analyzed. 
3. Right-click on the selection. 
4. Choose Reprocessing in the pop-up menu.

Reprocessing: Peak Integration

5. In the Reprocessing table, select the lowest standard. 
6. Select the integration button under the Evaluation section.
7. Left click and drag on the Chromatogram to zoom in on the baseline integrations of all the peaks. 
8. Increase or decrease Smoothing to increase or decrease the integration start and end lines on each peak. 
9. Click Update after any change to see it applied to the chromatogram. 
10. Increase or decrease the Sensitivity to have smaller peaks integrated or excluded from integration. 
11. Click the Peak Detection tab to use Minimum Height and Minimum Area to further adjust the height/area of peaks included or excluded from integration. 

Reprocessing: Component Labeling/Retention Times

11. In the Components button of Evaluation parameters, Components labeling and retention times can be updated. 
12. Click on the line of the component table for an ion. 
13. Left click on the peak for that ion. This center the retention time on the apex of the peak. 
14. Click on the update retention time button. The time on the Component table will be updated. 
15. Click the Update button to see these changes reflected on the Chromatogram. 
16. Repeat steps 12-15 for each component ion. 
17. If a peak is mislabeled, relabel the unidentified peak first, then hit Update. 
18. Now, update the retention times for the peak which was mislabeled. 

Reprocessing: Calibration Concentrations

19. Click the Standards button to enter the concentrations of standards, check standards, and matrix spikes. 
20. To edit existing concentrations for a particular standard, double click on that standard to edit. 
21. Update the calibration concentrations, pressing the tab key to move from one concentration to the next. 
22. If all component ions have the same concentration, enter the value in the first field, then click Filing. 
23. Use the single arrow to advance through standard levels and update these standard concentrations. 
24. At the end of the list use the single right arrow to add another standard level. 
25. Once completed, click the OK button. 
26. Repeat steps for Check standards and Spiking solutions as needed. 

Reprocessing: Calibration Curves

27. To edit the Calibration type utilized, click the Calibration button. 
28. Double left click on the line for a particular ion to edit the Response type used, the Curve type and the Weighting. 
29. Use the single arrows at the bottom of the window to advance to the settings for each ion, making changes as appropriate. 
30. Click OK once complete. 

Reprocessing: From Standards of Table

31. To reprocess the changes made to Standard 1 across all other calibration levels and create a new calibration graph, select Reprocessing. 
32. Choose from standards of reprocessing table. 
33. If you have made any manual integration changes, be sure to keep the Keep Manual Integration box checked. 
34. Click OK. 

Reprocessing: Evaluate Calibration Curves

35. Now select the last standard in the Reprocessing table, which is usually the highest calibration standard. All calibration points should be represented in this standard.
36. Click the Calibration Curve button.
37. Use the up and down arrow to scroll through the calibration graph for each analyte or use the pull-down menu to select the calibration graph for a particular analyte.
38. Evaluate the calibration for Relative Standard Deviation and Correlation Coefficient, based on the criteria of your application.

Reprocessing: From Selected Determination

39. Highlight the last standard.
40. Click Reprocessing.
41. Choose from Selected Determination.
42. Press OK. This will apply the full calibration to all standards.

Reprocessing: Save Calibration to Method

43. Save this new calibration to the method by selecting, Method → Save as.
44. Now either:
    1. Select name of the original method. A new version of the method will be generated (new version number). Can revert to previous versions using the History in the Method manager.
    2. Give the method a new name. Be aware if choosing this option the new method name will need to be chosen when running the next Determination series.
45. Click Save.

Reprocessing: Save to Data

The reprocess window is a "sand box". If the changes made are not saved to the data, they will be discarded. 

46. Clicking the red “X” button, or Cancel, will discard the changes.
47. Clicking OK saves these calibration changes to the determinations shown in the Reprocessing table (e.g. the standards).

Reprocessing: Apply New Calibration to Samples

To apply a new calibration generated in reprocessing to a series of samples already run: 

48. Highlight the highest calibration standard, then select along with it a block of data to apply it to. It is best to choose blocks of 20 determinations or less at a time to reprocess.
49. Select Reprocess.

Reprocessing: Apply New Calibration to Samples

50. Highlight the calibration standard (contains full calibration curve).
51. Select Reprocessing.
52. From Selected determination (applies full curve to all other determinations in reprocess window).
53. Click OK in the Reprocess sub window.
54. Click Ok in the main Reprocessing window to save these changes to the data.
55. Repeat steps 48-54 for blocks of ~20 determinations until all data desired has been reprocessed with the appropriate calibration.

Additional Support

If you encounter any issues or need additional help, please submit a support ticket through Metrohm Technical Support. 

For additional training on any of these topics, explore our available Metrohm Ion Chromatography Training courses or learn more about our Metrohm Custom Training options.