304 / 471
490
M
astovska
et al
.
:
J
ournal of
AOAC I
nternational
V
ol
. 98, N
o
. 2, 2015
separation for benzo[
b
]fluoranthene, benzo[
j
]fluoranthene,
and benzo[
k
]fluoranthene (concentration ratio of 1:1:1).
Note
:
Criteria for separation of chrysene and triphenylene (another
PAH critical pair) were not set for the collaborative study. For
accurate quantitation of chrysene, at least 50% valley separation
is recommended, which can be achieved using selective
stationary phases.
The maximum oven temperature program may not
exceed the maximum temperature limit for a given column.
Backbone-modified columns, such as Rxi-17Sil MS or
DB-17MS, are recommended for their better temperature
stability and also good selectivity for critical PAH pairs
or groups, including the anthracene/phenanthrene pair
or benzofluoranthenes. Conduct proper inlet and column
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 ben
benzo[
e
]pyrene (concentration ratio of 1:5), (
2
) at least 50% valley separ
phenanthrene and anthracene (concentration ratio 2.5:1; evaluated for
which is the second peak in the figure), and (
3
) at least 50% valley separ
benzo[
b
]fluoranthene, benzo[
j
]fluoranthene, and benzo[
k
]fluoranthene
of 1:1:1).
(3)
(2)
(1)
Figure 2014.08C. GC separation criteria: (1) A baseline separation
of benzo[
a
]pyrene and benzo[
e
]py ene (concentr tio ratio of 1:5),
(2) at least 50% valley s parati 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 r tio of 1:1:1).
Candidates for 2016 Method of the Year
245