AOAC Final Action Methods in 2018

(1)

Injection volume, µL 1 1 1 10 5

Table 2014.08G. ( continued ) Laboratory No. 6 7 8 9 10

Pressure pulse and duration NA NA 50 psi for 0.2 min NA NA

MS transfer line temperature, °C 300 280 320 300 325

PTV solvent vent pressure NA NA NA NA 50 kPa

Liner SGE, Focus liner Agilent, single taper, glass wool-packed, 4 mm id Agilent, double taper, 4 mm id Apex, ProSep taper liner, PTV solvent vent time NA NA NA NA 0.5 min 2 mm id 2 mm id

PTV solvent vent flow NA NA NA NA 100 mL/min

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

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

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

50°C (0.5 min), 600°C/min 400°C (15 min), 30°C/min 70°C Agilent, PTV multi-baffle,

(2)

Inlet temperature (program) 300 ° C 280°C 320°C 60°C (2.25 min), 300°C/min to 335°C (45 min)

(3)

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 (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). Figure 2014.08C. GC separation criteria: ( 1 ) A baseline separation of benzo[ a ]pyrene 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 anthrace 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 (concentrat of 1:1:1). Figure 2014.08C. GC separation criteria: (1) Abaseline separation of benzo[ a ]pyrene and benzo[ e ]pyrene

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