For research use only. Not for use in diagnostic procedures.

Answer

How to perform Positive charging test using Sciex OS® on 7500 instruments

Charging test is performed to assess the stability of sensitivity of the instrument over a period of time.
Fill in the syringe with fresh Tuning solution and connect the tubing to the source via the diverter valve.
From the home pane of Sciex OS® select MS Method

Create a method with the following POSITIVE polarity parameters and save it as Charging test 1.




Create a second method with the following NEGATIVE parameters and save it as Charging test 2.



Open the first method created called Charging test 1, change the duration to 15 min and save it as Charging test 3.



While on the MS method pane, click on the right-hand side to enable the syringe pump. Select the appropriate syringe type and set the flow to 10ul/min and start the syringe.



Next click on the Batch icon and create a batch with 3 samples. The first sample should have Method Charging Test 1, the second sample Charging Test 2 and the third sample Charging Test 3. Give the data file a name and submit the 3 samples to the queue. The acquisition should start immediately.



As soon as all 3 samples have been acquired open the last sample on explorer and observe the total ion count first and then by clicking Show-Extracted ion chromatogram, the individual ion count. There should NOT be a drop higher than 10% on the ion count of each trace.

Example of good charging test:




Example of failing charging test: