PlasmaQuant MS product family
Method optimization
83
Ensure the instrument has been warmed up for 15 minutes before starting the
optimization procedure. During the warm-up period, a time scan should be run to
ensure that the quadrupole is scanning.
1.
Open a system setup worksheet, or create a new worksheet. Click on [E
DIT
M
ETHOD
]
and select the analytes/isotopes of interest from the E
LEMENT
page.
2.
Go to the
OPTIMIZATION
page by clicking on the O
PTIMIZATION
tab in E
DIT
M
ETHOD
window and tune the instrument by adjusting the ion optics and plasma settings.
Alternatively, you can copy all (or partially) the method parameters from an
existing worksheet to a newly created worksheet.
3.
Open the S
CAN
S
ETUP
window by clicking [T
IME
S
CAN
S
ETUP
] on the
OPTIMIZATION
page. Set up reference and interference isotopes to be used for the iCRC-gas flow
rate optimization (see table below). E.g. for
75
As set
89
Y as a reference ion and
40
Ar
35
Cl
+
as interfering ion.
Also set up the ratio between reference and interference ion, i.e.
89
Y/
40
Ar
35
Cl
+
, to
be monitored as a signal to background level during the optimization.
Analyte
Interference
Reference
Recommended iCRC gas
51
V
+
35
Cl
16
O
+
45
Sc
+
He
52
Cr
+
40
Ar
12
C
+
35
Cl
16
O
+
H
+
45
Sc
+
He or H
2
56
Fe
+
40
Ar
16
O
+
45
Sc
+
H
2
75
As
+
40
Ar
35
Cl
+
89
Y
+
He or H
2
78
Se
+
40
Ar
38
Ar
+
89
Y
+
H
2
80
Se
+
40
Ar
40
Ar
+
89
Y
+
H
2
Click [OK] to close the Scan Setup window.
4.
Start the time scan in the optimization page by clicking [S
TART
] and at the prompt,
present the iCRC tuning Solution A.
Monitor the sensitivity changes in the time scan graph (in the Optimization
window), allowing time for the solution to reach the nebulizer and stabilize.
5.
Turn on the skimmer gas by selecting an appropriate gas source (selections from
OFF,
H2 or H
E
) in the iCRC parameters area.
6.
Adjust the iCRC skimmer gas flow rate manually using the up and down arrows to
achieve the optimal sensitivity ratio between the reference and interference.
Always monitor the background (or interference) level, and make sure there is no
significant increase in the background signals. The background signal measured in
Solution A should be less than 100 c/s.
Optimization