AOAC-RI ERP Book - FAOM METHOD.pdf

492 M ASTOVSKA ET AL . J OURNAL OF AOAC I NTERNATIONAL V OL . 98, N O . 2, 2015

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Table 2014.08I. PAH analytes and corresponding 13 C -PAHs used for PAH signal normalization Analyte

13 C 3$+ XVHG IRU VLJQDO QRUPDOL]DWLRQ

$QWKUDFHQH 13 C 6

Anthracene

Benz[ a @DQWKUDFHQH 13 C 6 Benzo[ a @S\UHQH 13 C 4 Benzo[ b @ÀXRUDQWKHQH 13 C 6 Benzo[ g,h,i @SHU\OHQH 13 C 12 Benzo[ k @ÀXRUDQWKHQH 13 C 6

Benz[ a ]anthracene

Benzo[ a ]pyrene

Benzo[ b @ÀXRUDQWKHQH Benzo[ g,h,i ]perylene Benzo[ k @ÀXRUDQWKHQH

&KU\VHQH 13 C 6

Chrysene

Dibenz[ a,h @DQWKUDFHQH 13 C 6

Dibenz[ a,h ]anthracene

)OXRUDQWKHQH 13 C 6

)OXRUDQWKHQH

)OXRUHQH 13 C 6

)OXRUHQH

Indeno[1,2,3- cd @S\UHQH 13 C 6

Indeno[1,2,3- cd ]pyrene

1DSKWKDOHQH 13 C 6 3KHQDQWKUHQH 13 C 6

Naphthalene Phenanthrene

3\UHQH 13 C 6

Pyrene

1DSKWKDOHQH 13 C 6 3KHQDQWKUHQH 13 C 6 3KHQDQWKUHQH 13 C 6 3KHQDQWKUHQH 13 C 6

1-Methylnaphthalene 2,6-Dimethylnaphthalene 1-Methylphenanthrene 1,7-Dimethylphenanthrene

&KU\VHQH 13 C 6

3-Methylchrysene

RI WKH LQVWUXPHQW 9HULI\ LGHQWL¿FDWLRQ RI WKH DQDO\WH SHDNV E\ FRPSDULQJ WKH LRQ UDWLRV RI FRQWHPSRUDQHRXVO\ DQDO\]HG FDOLEUDWLRQ VWDQGDUGV ZKLFK KDYH EHHQ DQDO\]HG XQGHU WKH VDPH conditions. ( c ) Injection sequence. ²%UDFNHW WKH VHYHQ WHVW VDPSOHV ZLWK WZR VHWV RI FDOLEUDWLRQ VWDQGDUGV ,QMHFW VROYHQW EODQNV DIWHU WKH FDOLEUDWLRQ OHYHO KLJKHVW VWDQGDUG DQG DIWHU WKH VDPSOHV ,Q DGGLWLRQ DQDO\]H D UHDJHQW EODQN ZLWK HDFK VHW RI VDPSOHV ,QMHFW RQO\ RQFH IURP HDFK YLDO WKXV SUHYHQWLQJ SRWHQWLDO ORVVHV RI YRODWLOH 3$+V DQG RU FRQWDPLQDWLRQ 4XDQWL¿FDWLRQ LV EDVHG RQ OLQHDU OHDVW VTXDUHV FDOLEUDWLRQ RI DQDO\WH VLJQDOV S PAH GLYLGHG E\ VLJQDOV S & 3$+ ) RI FRUUHVSRQGLQJ & ODEHOHG LQWHUQDO VWDQGDUGV see Table 2014.08I ) plotted versus analyte concentrations. 3HDN DUHDV DUH JHQHUDOO\ SUHIHUUHG DV VLJQDOV XVHG IRU WKH TXDQWL¿FDWLRQ EXW SHDN KHLJKWV VKRXOG EH XVHG IRU SHDNV WKDW are not well resolved, such as in the case of anthracene and SKHQDQWKUHQH 7KH DQDO\WH FRQFHQWUDWLRQV LQ WKH ¿QDO H[WUDFW ( c PAH —J / DUH GHWHUPLQHG IURP WKH HTXDWLRQ c PAH > S PAH S & 3$+ ± b @ a where a is the slope of the calibration curve and b is the y LQWHUFHSW The concentration of PAHs in the sample ( C —J NJ LV WKHQ FDOFXODWHG C = ( c PAH c & 3$+ î X & 3$+ m ) where c & 3$+ LV WKH FRQFHQWUDWLRQ RI WKH FRUUHVSRQGLQJ & 3$+ LQ WKH FDOLEUDWLRQ VWDQGDUG VROXWLRQV LQ —J / H. Calculations

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