Calibrating in REM Mode

To Calibrate the MRT in REM Mode

From the Tune page:

1. Select Tune.
2. Select the required mass range.

3. Infuse the calibrantion solution of choice into the MRT, and then ensure that the reference ions are observed.

NOTE:    When choosing a calibration compound, a large number of reference ions across the calibration profile m/z range will achieve greatest mass accuracy. The upper and lower m/z should be also be as close to the m/z range limits as possible. i.e. in the screenshot shown, greatest mass accuracy will be achieved for ions falling within the 248 to 588 m/z range.

4. Click Acquire to calibrate, in this case sodium formate, over the selected mass range.
5. Click abort once the acquisition has finished.

6. In the Acquisition Settings window, enter a filename and Acquisition time for the mass calibration, and then select Save to acquire the data to be used to perform mass calibration.

IMPORTANT: Ensure that you select the "Retain Data for Mass Calibration" tick box.

7. Select manual calibration.

NOTE: Before acquiring the mass calibration, click Abort to ensure that the instrument is not in Tune or acquiring data.

8. Select the required REM mass calibration range.
9. Click Create.

10. Check the data residuals (Mean prediction error <0.2 ppm), and then click Accept if acceptable.

NOTE: A successful calibration over the required mass range and polarity will be indicated.