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Simplify PAH Analysis
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Results in Table I demonstrate that good recoveries were obtained under these preliminary con-
ditions, especially considering that hydrophobic compounds were being extracted in hydrophilic
QuEChERS solvent. High recoveries were noted for some compounds (e.g. fluoranthene), but
were not due to isobaric interference as evidenced by high efficiency separation of PAHs from
matrix (Figure 2) and by good agreement between sample and reference spectra (Figure 3).
Conclusion
Combining QuEChERS extraction with GCxGC-TOFMS, using Rxi®-17Sil MS and Rxi®-1ms
columns shows great promise for analyzing PAHs in seafood. Labs interested in alternatives to
the NOAA method should consider procedures based on this approach.
Visit our technical blog at for more details.
Table I Preliminary conditions gave
good recoveries for most PAHs (n = 3).
Average
Q NIST µg/kg by
PAH Mass µg/kg GCxGC RSD%
Naphthalene-D8 136 ISTD ISTD ISTD
Naphthalene 128 9.68 63 5
2-Methylnaphthalene 142 8.1 8.6 15
1-Methylnaphthalene 142 5.8 5.4 8
Biphenyl 154 NA 4.2 1
2,6-Dimethylnaphthalene 156 NA 9.1 3
Acenaphthylene 152 NA 1.7 18
Acenaphthene-D10 162 ISTD ISTD ISTD
Acenaphthene 154 NA 3.3 22
2,3,5-Trimethylnaphthalene 170 NA 4.0 13
Fluorene 166 NA 8.8 8
Phenanthrene-D10 188 ISTD ISTD ISTD
Phenanthrene 178 74.4 113 5
Anthracene 178 2.46 8.1 8
1-Methylphenanthrene 192 17.6 29 12
Fluoranthene 202 287 376 5
Pyrene 202 186 229 4
Benzo(a)anthracene 228 31.1 39 9
Chrysene-D12 240 ISTD ISTD ISTD
Chrysene 228 123.6 199 5
Benzo(b)fluoranthene 252 41.5 53 0
Benzo(k)fluoranthene 252 18.95 22 12
Benzo(j)fluoranthene 252 21.4 18 3
Benzo(a)pyrene 252 9.73 12 5
Perylene-D12 264 ISTD ISTD ISTD
Perylene 252 6.80 5.0 3
Indeno(1,2,3-cd)pyrene 276 14.9 13 1
Benzo(ghi)perylene 276 23.7 20 10
ISTD = internal standard
NA = not analyzed by NIST
Figure 2 GCxGC-TOFMS contour plot of PAHs in mussels (QuEChERS extraction).
*Maximum temperatures listed are for 15- and 30-meter
lengths. Longer lengths may have a slightly reduced
maximum temperature.
ID df (µm) length qty. cat. #
0.18mm 0.18µm 20m ea. 14102
0.18mm 0.36µm 20m ea. 14111
0.25mm 0.25µm 15m ea. 14120
0.25mm 0.25µm 30m ea. 14123
0.25mm 0.25µm 60m ea. 14126
0.32mm 0.25µm 15m ea. 14121
0.32mm 0.25µm 30m ea. 14124
Rxi®-17Sil MS Columns (fused silica)
(midpolarity Crossbond® silarylene phase;
equivalent to 50% phenyl methyl polysiloxane)
temp. limits: 40 to 340/360°C
Column: Rxi® -17Sil MS 30 m, 0.25 mm ID, 0.25 µm (cat.# 14123); Rxi®-1ms 1.2 m, 0.15 mm ID, 0.15 µm (cat.# custom);
Sample: NIST SRM 2974a freeze-dried; mussel tissue with incurred residues; Diluent: Acetonitrile.
For complete conditions visit and search for GC_FF1197.
Figure 3 Good agreement
between sample and reference
spectra show target PAHs were
separated from isobaric
interferences.
Column:
Rxi ®-17Sil MS 30 m, 0.25 mm ID, 0.25 µm
(cat.# 14123);
Rxi ®-1ms 1.2 m, 0.15 mm ID, 0.15 µm
(cat.# custom);
Sample: NIST SRM 2974a freeze-dried
mussel tissue with incurred residues;
Diluent: Acetonitrile.
For complete conditions visit
and search for GC_FF1198.
PAH lists vary among
methods and labs.
Visit
for a complete list of
stock products, or to
order a custom mix.
PAH
5
sec.
A. Caliper spectrum
B. Deconvoluted spectrum
C. Reference spectrum
For Q-sep™ QuEChERS product
information, see page 7 or visit
Website : E-mail : TelNo : 03 9762 2034 . . . in AUSTRALIA