Displaying Calibration Curves
Validating the Calibration Curve

To check the calibration using the respective values of the Validation Samples (perhaps of the standard sample as well) you have to compare the expected concentration or amount values to the measured/calculated values either numerically by means of the Amount Deviation report variable or visually by means of the calibration function.

1. Numerically, by means of the Amount Deviation report variable:

The determined (actual) area values are converted to concentration or amount values by means of the Calibration Function and compared to the expected (nominal) values of the Amount table.

• Add a new column to a report or a Printer Layout page or change the assignment of an existing column as described in Creating and Using Report Tables  Defining the Contents of a Report.

• Select the Amount Deviation variable in the Peak Results report category. Click Parameter to define whether the result of the variance comparison shall be expressed as absolute amount value or as deviation in percent (Relative in % of the expected Amount).

2. Visually, by means of the Calibration Curve

For checking the calibration curve visually, the validation samples can be displayed (specially marked) in the curve:

• Select Decoration on the context menu of the calibration curve (respectively, the Calibration Plot Properties command in the Printer Layout).

• Select the Draw validation sample points check box on the Options tab page.

 Note:

Even if this action is performed in the QNT Editor, these validation samples will not be considered for the calibration. Nevertheless, if you wish to use a validation sample as standard sample later and consider it for calculating the calibration curve, set the Type (Sample Type) to Standard in the sample list of the Browser.

3. By Means of the Confidence Interval

1. In addition, the confidence region interval can be indicated in the calibration curve. Select the Draw upper and lower confidence limit check box on the Options tab page and define the confidence region to check whether your validation and standard samples are within the corresponding confidence interval (also, refer to Displaying Calibration Curves  Indicating the Confidence Interval).

2. For single values, you can also indicate the limits for the respective Confidence Interval in the Report using the Upper/Lower Confidence Limit variables of the Peak Calibration report category.

For information about how to enter the concentration/amount, refer to Integrating Chromatograms and Identifying Peaks  Entering the Concentration/Amount of the Validation Sample.

For an overview of the different calibration possibilities provided by Chromeleon, refer to  Calibrating.