Agilent 7890a gc with 5975c msd

The samples were concentrated to 0.5 mL under nitrogen evaporation. The content of 16 priority PAHs including naphthalene, acenaphthene, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, indeno(1,2,3-cd)pyrene, dibenzo(a,h)anthracene and benzo(g,h,i) perylene were determined using gas chromatography-mass spectrometry (GC/MS) (Agilent 7890A GC with 5975C MSD, Agilent Technology). The injection was done in on-column mode. The transfer line was set to 300 °C. The temperature program was: 99 °C for initial temperature, 2 °C min⁻¹ to 310 °C for 34 min. Gas flow (He) 1.1 mL min ⁻¹. The analysis was conducted with a 60 m column (DB-5MS, 250 μm, 0.25 μm), using QTM 16-PAHs mix (CRM47930, Sigma-Aldrich) as a standard. The LODs and LOQs of the 16 PAHs were 0.07–0.15 μg mL⁻¹ and 0.20–0.45 μg mL⁻¹, respectively. To ensure the accuracy and precision of this study's individual PAHS analysis process, a seven-point calibration standard (linearity R² > 0.99; 0.5–12.5 μg mL⁻¹) in solution, detection limits and procedural blank were carried out. Each calibration standard and sample contained an internal standard (100 μL of phenanthrene-d10 at a concentration of 40 μg mL⁻¹). The recoveries ranged from 76 to 102% for individual PAHs. The reported results have been corrected for losses.

Air-dried NaX–FA, NaX–Ver, and NaX–C samples (7.00 ± 0.02 g) were mixed with 100 mL of n-hexane/acetone, 1:1 (v/v), (Chempur reagent grade 99%) at room temperature and extracted using FOSS Soxtec Avanti 2055. To all of the samples, 100 μL of deuterated phenanthrene-d10 (Sigma-Aldrich, St. Louis, MO, USA) at a concentration of 2000 µg mL⁻¹ in dichloromethane (DCM) as an internal standard was added. The solutions after Soxtec extraction were concentrated to a volume of 0.5 cm³ under nitrogen evaporation. The extracts were passed through a column containing activated silica gel topped with 5 g of anhydrous sodium sulfate. The air-dried samples after Soxtec extraction were solved with 4 mL of hexane and eluted with two portions (8 mL) of a mixture of hexane/DCM, 1:1 v:v, and analyzed by GC-MS (Agilent 7890A GC with 5975C MSD, Santa Clara, CA, USA). The injection was carried out in on-column mode. The transfer line was 300 °C. The temperature program was 99 °C for the initial temperature and 2 °C min⁻¹ to 310 °C for 34 min. Gas flow (He) was 1.1 mL min ⁻¹. The analysis was conducted with a 60 m column (DB-5MS, 250 µm, and 0.25 µm), using QTM 16-PAHs mix (CRM47930, Sigma-Aldrich) as a standard. The experiments were carried out in triplicate.