Optimization of Resolving Power, Fragmentation, and Mass Calibration in an Orbitrap Spectrometer for Analysis of 24 Pesticide Metabolites in Urine
Table 5
Average mass accuracies (∆m) (ppm) and standard deviations (Std dev) using internal and external calibration for diagnostic and fragment ions in ESI positive mode (n=5).
Metabolite
Diagnostic ion
Fragment ion
Internal calibration
External calibration
Internal calibration
External calibration
∆m (ppm)
Std dev
∆m (ppm)
Std dev
∆m (ppm)
Std dev
∆m (ppm)
Std dev
DEAMPY
0.21
0.13
0.47
0.26
0.17
0.08
1.15
0.19
IMPY
0.08
0.06
0.62
0.26
3.55
0.08
2.64
0.23
DIMET
0.27
0.07
0.76
0.29
0.44
0.05
0.50
0.12
OMET
0.14
0.10
0.53
0.39
0.12
0.11
0.90
0.33
AP
0.12
0.10
0.41
0.21
0.15
0.08
0.99
0.27
ATZM
0.49
0.15
0.99
0.41
0.19
0.04
0.91
0.36
ALAM
0.24
0.27
1.14
0.55
0.17
0.14
0.59
0.17
METM
1.52
1.38
2.23
1.07
0.77
0.45
1.96
0.39
Acquisition conditions: ESI+/ESI- in the same injection, R = 25,000 FWHM, and CID fragmentation 40 eV.
