Creating a Precursor Ion Method for Triple Quadrupole LC/MS Systems with MassHunter 12.0 or Later

Answer

This information applies to: Agilent Triple Quadrupole LC/MS System, MassHunter 12.0 or later.

Issue

Set up a precursor ion acquisition method.

Steps to Follow

1. From the Scan type drop-down list in the Time Segments window, select Precursor Ion (Figure 1).
   

   
   
   Figure 1. Scan Type drop-down list
   
   

2. Fill the table with the different information (Figure 2):
   • Segment name: The name to use for this scan segment.
   • Compound Formula: The formula of the compound; used for the quantification method.
   • Ion Species: The ion species of the compound. Some examples of Species are (M+H)⁺ and (M+Na)⁺.
   • CAS: Chemical Abstracts Service number.
   • z: The charge of the compound.
   • Product m/z: The mass over charge of the product ion to acquire.
   • MS2 res: The desired resolution of the second quadrupole. It matches the tune file peak widths.
   • Start m/z: The beginning mass of the scan for the product ion.
   • End m/z: The end mass of the scan for the product ion.
   • Scan Time: The time to spend in milliseconds (ms) to scan this scan segment before switching to the next scan segment.
   • Fragmentor: The voltage (V) of the fragmentor.
   • CAV: The voltage (V) for the cell accelerator.
   • CE: The voltage (V) for the collision energy.
   • Polarity: The polarity of the triple quadrupole to acquire this transition. 
     

     
     
     Figure 2. Acquisition Parameters table
     
     

3. Add and remove lines using appropriate icons .
4. The bottom of the table has some information and parameters to set (Figure 3):
   • Estimated cycle time: How long it takes in milliseconds (ms) to complete a cycle of all the scan segments.
   • Estimated max scan speed: How fast the data are acquired.
   • Data storage: Select the location to store data, either in Centroid or in Profile.
   • Threshold: If Profile is selected, the Threshold value does not change anything. If Centroid is selected, the Threshold value is there to limit what will be added to the data file. Anything under that value will not be saved, thus reducing the data file size.
     

     
     
     Figure 3. Acquisition Parameters table parameters
     
     

5. Add a desired Start time, Detector Gain Factor for the positive, and negative polarity and if that time segment is to be Stored to the data file (Figure 4).

   
   
   Figure 4. Time Segments table
   
   

6. Save the method as or overwrite the currently loaded method .

Learn how to effectively operate your Agilent MassHunter 12 for Triple Quadrupole LC/MS:  Agilent Triple Quadrupole LC/MS System Introduction Workbook user manual on Agilent.com Agilent Triple Quadrupole LC/MS System User Guide user manual on Agilent.com