## 3 Sample Treatment and Analysis Methods
### Analytical Methods
\begin{tabular}{l l} \hline \hline \hline \multicolumn{1}{c}{**Compounds**} & \multicolumn{1}{c}{**Sample and Treatment**} & \multicolumn{1}{c}{**Analysis Method**} & \multicolumn{1}{c}{**Recovery and LOD**} & \multicolumn{1}{c}{**Ref.**} \\ \hline \hline
6 NPAHs (2-NF, 9-NAnt, 3-NF, 1-NF, 6-NC), 16 PAHs. & River water, groundwater, seawater, rainwater. DLIME with acetonitrile (dispersive solvent), chloroform & & Recoveries: 83-119-, 1-9-NAnt and 1-NF were detected in environmental water & [33] \\
1-NF & 7-NBaA, 6-NC, 16 PAHs. & Drinking water, snow, sausage, meat. & & \\
5-Nace, 2-NFs, 2-9, 9-NAnt, 3-, & SPME with core-shell discoid shape & & \\
9-NPs, 2-3-NPs, 1-NF, 7-NBaA, 6-CNBaP & N2S360 ML-125(II) nanocomposite. & GC-MS, NCI. & & \\ \hline
10 NPAHs (2-NNap, 2-Nbp, 5-Nace, 2-NF, 9-NAnt, 9-NN, 1-NP, 2-NPR, 6-NC). & SDME (mico extractor) with polymethylsiloxane/divinylbenzene (1 cm \(\times\) 65 mm), 7-100 \(\mu\) PDMS, 85-nm polyacrylate \(\rightarrow\) GC-MS & & Recoveries: 69.1–110.1\% (PDAMS/(DVS), LOD\(\times\) 0.007–0.063 \(\mu\)g L\({}^{-1}\).) & [35] \\
2-7-DNE, 6-NC). & & & \\ \end{tabular} \begin{tabular}{l l} \hline \hline \hline \multicolumn{1}{c}{**GC-Quadrupole MS.**} & \multicolumn{1}{c}{**Recoveries: 69.1–110.1\%**} & \multicolumn{1}{c}{} \\ \hline
6 NPAHs (2-NNap, 2-Nbp, 5-Nace, 2-NF, 9-NAnt, 1-NP, 2-NPR, 6-NC). & & & \\ \hline
6 NPAHs (2-NNap, 9-NAnt, 9-NN, 1-NF, 6-NC). & & & \\ \hline  & & & \\ \end{tabular} 
\begin{tabular}{l l} \hline \hline \hline \multicolumn{1}{c}{**GC-Quadrupole MS.**} & \multicolumn{1}{c}{**Recoveries: 66.3–104.6\%**, 1.00\%-1.0\%-1. developed to reduce NPAHs to their APAH congeners prior to HPLC analysis [48]. A short column packed with Pt/Rh has also been incorporated as an on-line reducing agent [49]. A similar on-line reducing column has been used in the analysis of NPAHs with HPLC-FL [50]. 21 NPAHs in particulates emitted from diesel vehicles were identified simultaneously using HPLC-CL [51]. Recently, by modifying separation and detection conditions of the system, the simultaneous determination of PAHs and NPAHs has been achieved [52]. LC-MS/MS coupled with APCI has been used in the analysis of NPAHs in aqueous samples [32; 53]. High-resolution MS is effective in identifying unknown compounds. For this reason, the quadrupole Orbitrap LC-MS has attracted attention in the research field of environmental NPAHs [54; 55; 56]. LC-Orbitrap-HRMS with negative ESI-mode identified seventy-three NPAHs in urban atmospheric PM\({}_{2.5}\)[57]. In the last two decades, by using mass spectrometry-based methods coupled with several pre-treatment methods, research concerning environmental and biological NPAHs has increased. GC-EI-MS/MS, GC-NICI-MS/MS and LC-ESI-MS/MS were effectively used for simultaneous determination of NPAHs and OPAHs in soil and sediment samples [58; 59]. As one in situ analytical method, the fluorescence quenching monitoring of NPAHs on crop leaf surfaces has been demonstrated by fiber-optic fluorometry (FOF) coupled with graphene quantum dots (GQDs) [60]. \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline \multicolumn{2}{p{113.8 pt}}{**Compounds**} & \multicolumn{1}{p{113.8 pt}}{**Sample**} & \multicolumn{1}{p{113.8 pt}}{**Analysis Method**} & \multicolumn{1}{p{113.8 pt}}{**LOD and Recovery**} & \multicolumn{1}{p{113.8 pt}}{**Ref. **} \\ \hline
14 NPAHs (1-NN2; 2-NBPs; 5-NAce; 2-NF; 9-NrHs; 9-NAnt; 3-NFR; 1-NP; 2-7-DNF; 6-NCP; 1-3-1, 1-6-, 18-DNPs; 6-NBaP) & PM\({}_{2.5}\). Direct injection of GFF. & GC-NICI-MS. Injection port: 280 \({}^{\circ}\)C, Thermal desorption, Capillary column: HP-5 MS, 30 m \(\times\) 0.25 mm i.d. & Recoveries 77–106\% except 6-NBaP. & [46] \\ \hline
3 NPAHs (9 NAnt; 3-NFR; 1-NP), & Extracts from PM\({}_{2.5}\). & GC-multiphoton ionization time-of-flight mass spectrometry (TOF-MS). On-line chemical reduction of NPAHs to amino derivatives using hydrazine & & \\  & & & & \\  & & & & \\