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M
ASTOVSKA
ET AL
.:
J
OURNAL OF
AOAC I
NTERNATIONAL
V
OL
.
98, N
O
. 2, 2015
487
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F. Extraction and Cleanup Procedure
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dependent on the silica deactivation,
see Note
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the eluent.
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cleanup step.
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), thus the evaporation should
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volume, i.e., until only the isooctane and coextracted fat are left
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is recommended for a better control of the evaporation process
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the silica, thus its potentially different retention characteristics.
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fat and determine the optimum volume of the elution solvent
to ensure adequate analyte recoveries and fat cleanup. The
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Table 2014.08D. (
continued
)
PAH
1R RI
laboratories 1R RI UHSOLFDWHV
Mean
concn, μg/kg
Mean recovery,
% s
r
, μg/kg s
R
, μg/kg RSD
r
, % RSD
R
, % HorRat
9
18
Naph
9
18
9
18
8
16
Phe
9
18
9
18
8
16
Pyr
9
18
8
16
9
18
10 g of homogenized sample
- Add
13
C-PAH mixture, vortex, equilibrate (15 min)
Extraction:
- Add 5 mL (or 10 mL) water and 10 mL EtOAc, shake (1 min)
- Add 4 g anh. MgSO4 and 2 g NaCl, shake (1 min), centrifuge
- Evaporate 5 mL aliquot of extract, reconstitute in 1 mL hexane
Silica-SPE clean-up:
-
Condition 1g silica with 6 mL hexane:DCM (3:1,
v/v
) and 4 mL
hexane
-
Apply sample
-
Elute with 10 mL of hexane:DCM (3:1,
v/v
)
GC-MS(/MS) analysis
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PAHs in seafood using GC/MS.