Agilent 8900 replicate instability in O2 mode

Hello Agilent community,

We have observed systematic drift between replicates within any given measurement of element counts in O2 mode. An example of this is shown in the figure below (showing five separate measurements of the same sample with five replicates performed during each measurement). We do not see this systematic drift in any other gas mode (see No gas figure also below from the same run). 

For this run the stabilization time for the O2 mode was set to 30 seconds. Tuning parameters for the cell are:

O2 gas flow: 20%

OctP Bias: -3 V

Axial Acceleration: 1 V

OctP RF: 180 V

Energy discrimination: -8 V

Any insight would be much appreciated.


Was this helpful?