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are recommended (e.g., ≥280°C for Agilent sources) to provide
optimum analysis (quantitative transfers, minimum peak tailing)
for less volatile PAHs.
Table
2014.08H
provides MS ions (
m/z
) and MS/MS transitions
used by the study participants for quantification and identification
of target PAHs and
13
C-PAHs using single-stage MS (single
quadrupole and TOF) and tandem MS/MS (triple quadrupole)
instruments, respectively.
Use adequate data acquisition rate (dwell times in scanning
instruments) and solvent delay time. Perform air/water checks and
autotune to verify and obtain adequate operation of the instrument.
Verify identification of the analyte peaks by comparing the ion
Table 2014.08G. (
continued
)
Laboratory No.
6
7
8
9
10
He flow/pressure program
1.5 mL/min (13 min),
10 mL/min
2
to 2 mL/min
1.5 mL/min (constant flow)
1 mL/min (constant flow)
1.3 mL/min (19.5 min),
50 mL/min
2
to 2 mL/min
2 mL/min (constant flow)
Injection mode
Hot splitless
Hot splitless
Pulsed splitless
Splitless
PTV solvent vent
Injection volume, µL
1
1
1
10
5
Inlet temperature (program)
300
°
C
280°C
320°C
60°C (2.25 min), 300°C/min
to 335°C (45 min)
50°C (0.5 min), 600°C/min 400°C
(15 min), 30°C/min 70°C
Liner
SGE, Focus liner
Agilent, single taper, glass
wool-packed, 4 mm id
Agilent, double taper, 4 mm id
Apex, ProSep taper liner,
2 mm id
Agilent, PTV multi-baffle,
2 mm id
PTV solvent vent time
NA
NA
NA
NA
0.5 min
PTV solvent vent flow
NA
NA
NA
NA
100 mL/min
PTV solvent vent pressure
NA
NA
NA
NA
50 kPa
Pressure pulse and duration
NA
NA
50 psi for 0.2 min
NA
NA
Split vent purge flow and start
50 mL/min, 1 min
50 mL/min, 1 min
50 mL/min, 1 min
50.0 mL/min, 2.30 min
100 mL/min, 3 min
Gas saver flow and start time
20 mL/min, 3 min
20 mL/min, 2 min
15 mL/min, 6 min
NA
15 mL/min, 6 min
MS transfer line temperature, °C
300
280
320
300
325
Figure 2014.08C. GC separation criteria: (
1
) A baseline separation of benzo[
a
]pyren
benzo[
e
]pyrene (concentration ratio of 1:5), (
2
) at least 50% valley separation of
phenanthrene and anthracene (concentration ratio 2.5:1; evaluated for the anthrac
which is the second peak in the figure), and (
3
) at least 50% valley separation for
benzo[
b
]fluoranthene, benzo[
j
]fluoranthene, and benzo[
k
]fluoranthene (concentra
of 1:1:1).
(3)
(2)
(1)
Figure 2014.08C. GC separation criteria: (1) Abaseline
separation of benzo[
a
]pyrene and benzo[
e
]pyrene
(concentration ratio of 1:5), (2) at least 50% valley separation
of phenanthrene and anthracene (concentration ratio 2.5:1;
evaluated for the anthracene peak, which is the second
peak in the figure), and (3) at least 50% valley separation for
benzo[
b
]fluoranthene, benzo[
j
]fluoranthene, and benzo[
k
]
fluoranthene (concentration ratio of 1:1:1).
Candidates for 2016 Method of the Year
229