What is deflect tune mass? Agilent 8800 He gas mode


I am trying to measure Iron in the agilent 8800 using collision/reaction cell with He gas mode. In my tuning parameters I am using the Tuning solution and in my tuning parameters I am tuning for mu 59, 89 and 140. Its also asking for a deflect tune mass (by default its set as 89 mu). I dont exactly know what this value means and i cant find literature explaining this and what to put in it. Can somebody help?


  • Hello Kevin,

    For Fe you could also try measuring on H2 mode, theoretically you will get slightly better DL using this mode. Regardless of He/H2 mode you should be tuning your 8800 using the masses 59, 89 and 205. Of course you can still use mass 140 for the "high" mass in your tuning. Deflect is a lens straight after the collision cell. It will curve the trajectory of the ions coming out of the collision cell through the plate bias lens, so that only the charged species will enter Q2 and the neutrals will be rejected. As this is a very important lens we have to tune it and normally for He/H2 on ICPQQQ we are using mass 89. So the default setting is OK.

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