Skip to main content
Waters

What process and acceptance criteria are associated with ACQUITY QDa Detector for mass scale calibration and resolution? - WKB11532

Article number: 11532

ENVIRONMENT

  • ACQUITY QDa.

ANSWER

ACQUITY QDa Detector Resolution Background The ACQUITY QDa Detector quadrupole resolution is set up to ensure that mass data is acquired across the mass range at a nominal resolution of 0.7 Da Full Width Half Maximum (FWHM). This means that mass spectral peaks across the range will be approximately 0.7 Da wide at half the maximum height of the peak (see tolerance described below). It is possible to both set up and check the quadrupole resolution of the ACQUITY QDa Detector. The resolution setup is performed in both positive and negative ion modes. ACQUITY QDa Detector Resolution Setup Acceptance Criteria For a successful resolution The resolution setup experiment must set 4 out of 4 masses (4 for positive/4 for negative) across the mass range at a resolution of 0.7 Da Full Width Half Maximum (FWHM), with an acceptance criteria of ±0.2 Da. For both fast and slow scanning experiments; each peak must match the 0.7 Da peak width (with a tolerance of ±0.2). On completion of a successful resolution setup, the ACQUITY Console displays the new expiration date of the resolution (setup date 365 days). If unsuccessful, the resolution expiration date will be blank. After a completed resolution setup, a resolution check is performed to verify its success (see below). A re-run of the resolution setup instigates the requirement to perform the QDa mass scale calibration setup. ACQUITY QDa Detector Resolution Check Acceptance Criteria For a successful resolution check, the following criteria must be met: The resolution check experiment must confirm that 4 out of 4 masses (4 for positive/4 for negative) across the mass range have a resolution of 0.7 Da Full Width Half Maximum (FWHM) with an acceptance criteria of ±0.2 Da. Each peak must match the 0.7 Da peak width (within a tolerance of ±0.2) for both fast and slow scanning experiments. On completion of a successful resolution check, the expiration date shown in the ACQUITY Console will not be updated; it will still display the original expiration date of the resolution (setup date + 365 days). ACQUITY QDa Detector Mass Scale Calibration Background On all Waters single quadrupole and tandem quadrupole MS instruments the mass scale calibration setup is performed in a single ionization mode and applied to both positive and negative modes. Because this process calibrates the voltages applied to quadrupoles, it is independent of the polarity used. A successful calibration setup can be applied to each ionization mode. On the ACQUITY QDa Detector, the mass scale calibration is performed in negative ion mode. It is possible to both set up and check the mass scale calibration of the ACQUITY QDa Detector. ACQUITY QDa Detector Mass Scale Calibration Setup Acceptance Criteria For a successful calibration setup, the following criteria must be met: 15 out 20 calibration peaks must be within ±0.2 Da of the reference mass. After a completed calibration setup, a calibration check is performed to verify its success. On completion of a successful calibration setup, the ACQUITY Console displays the new calibration created date (calibration date) and the new expiration date of the calibration (calibration date + 365 days). If unsuccessful, the calibration created date shows as "Uncalibrated". ACQUITY QDa Detector Mass Scale Calibration Check Acceptance Criteria For a successful calibration check, the following criteria must be met: 4 out of 6 masses must be within ±0.2 Da of the reference masses On completion of a successful calibration check, the ACQUITY Console displays the original calibration created date and an updated expiration date of the calibration (calibration check date ÷ 365 days). If unsuccessful, the calibration date shows as "Uncalibrated" and the expiration date is blank.

ADDITIONAL INFORMATION

Not able to find a solution? Click here to request help.