How to recalibrate or add a peak to the existing calibration in Clarity chromatography software

Calibration is a crucial step in quantitative analytical chemistry, ensuring that the relationship between instrument response and analyte concentration remains accurate and reliable. However, during instrument operation, individual calibration levels may occasionally produce outliers that distort the overall calibration curve. This instructional guide provides a detailed procedure for manually recalibrating one or more levels for specific compounds when a correct standard has already been measured. 

Objective

To demonstrate how to correct a single calibration level (e.g., Level 3 of Compound B) that appears as an outlier by using a correctly measured standard. The recalibration procedure replaces the incorrect response value, resulting in a more accurate and reliable calibration curve.

Required Tools and Prerequisites

Before performing recalibration, ensure the following conditions are met:

• Software: DataApex Clarity Chromatography Software
• Access rights: User must have permission to modify calibration data.
• Measured standards: A valid chromatogram or data file from the correct standard measurement is available.
• Known target compound(s): Identification of the compound(s) requiring recalibration (e.g., “Compound B”).

Optional but recommended:

• Prior knowledge of the software’s Calibration Options settings.
• Familiarity with Add Peak and Calibration Curve visualization tools.

Step-by-Step Procedure

1. Identify the Outlier in the Calibration Curve

Begin by examining your existing calibration plot. Identify which compound and which level (e.g., Level 3 of Compound B) deviates significantly from the expected regression line.

Outliers often result from manual integration errors, incorrect concentration entries, or instrumental noise during standard measurement.

2. Open the Compound Record

1. Navigate to the Compounds tab in your software.
2. Select the correct standard that you plan to use for recalibration.
3. Confirm that the chromatographic data corresponds to the compound and calibration level you wish to correct.

3. Switch to Recalibration Mode

1. Ensure that the displayed compound level matches the desired calibration level (e.g., Level 3).
2. In the toolbar or menu, locate the Mode selection option and switch to Recalibration.

This mode allows the replacement of response data for specific calibration levels while preserving other calibration information.

4. Configure Calibration Options

1. Open the Calibration Options dialog.
2. Set the Recalibration Mode to Replace.
   • This ensures that the new measurement replaces the existing data point instead of averaging or appending it.
3. If needed, refer to your software’s reference video or manual section titled “How to Modify the Calibration Settings” for detailed configuration guidance.

5. Use the “Add Peak” Function

1. Click Add Peak.
2. Select the chromatographic peak corresponding to the compound you wish to recalibrate.
   • The Add Peak function inserts a single selected peak into the chosen calibration level.
3. Confirm your selection.
   • The system will automatically update the response value for the current calibration level.

6. Verify the Calibration Curve

Once the recalibration is complete:

1. Reopen the calibration curve view for the affected compound (e.g., Compound B).
2. Check that the curve now displays improved linearity and correlation.
3. If multiple compounds or levels require recalibration, repeat the process for each one.

7. Add New Compounds (Optional)

This same procedure can also be applied to add new compounds to an existing calibration series:

1. Enter the compound name and concentration (amount).
2. Use the Add Peak function to associate the appropriate signal with the correct level.
3. Repeat for each required calibration level.

Discussion and Best Practices

• Accuracy and validation: Always verify recalibrated results using a quality control sample or check standard to confirm that the calibration update improved analytical accuracy.
• Documentation: Record each recalibration event in the laboratory logbook or electronic data management system, noting the reason for adjustment and the file used.
• Automation caution: Avoid overreliance on automated recalibration features—manual review ensures that only valid data points are replaced.
• System suitability: Confirm that recalibration does not violate method validation requirements in regulated environments (e.g., GMP, ISO 17025).

Conclusion

Manual recalibration of individual calibration levels is a valuable technique for maintaining data integrity and analytical reliability. By using the Recalibration Mode, Calibration Options, and Add Peak functions, users can efficiently replace erroneous responses with accurate measurements from valid standards.

This targeted recalibration approach improves the precision of the calibration curve, extends instrument usability, and enhances confidence in quantitative results.

For additional training, tutorials, and troubleshooting resources, visit the official YouTube channel or user documentation provided by your software vendor.