5975c network mass spectrometer gc ms

Analyses were performed on a 7820A gas chromatograph coupled with a 5975C network mass spectrometer (GC–MS) (Agilent Technologies, Germany). Compounds were separated on an Agilent Technologies HP‐5 MS cross‐linked poly‐5% diphenyl–95% dimethyl polysiloxane (30 m × 0.32 mm i.d., 0.25 μm film thickness) capillary column. The column temperature was initially set at 45 °C, then increased at a rate of 2 °C/min up to 100 °C, then raised to 250 °C at a rate of 5°C/min and again raised up to 280 °C at a rate of 11 °C/min and finally held for 15 min. The injection volume was 0.1 μl, with a split ratio of 1:40. Helium was used as the carrier gas, at a flow rate of 0.7 ml/min. The injector, transfer line, and ion‐source temperature were 250, 280, and 230 °C, respectively. MS detection was performed with electron ionization at 70 eV, operating in the full‐scan acquisition mode in the m/z range 40–400. The sample was diluted 1:20 (vol/vol) with n‐hexane before GC–MS analysis. All reference standards used for GC analysis, chromatographic grade organic solvents and reagents were purchased from Merck KGaA (Germany).

The authors sent the samples to the Office of Scientific Instrument and Testing (OSIT), Prince of Songkla University, for GC–MS analysis. Accordingly, OSIT provided the authors with GC–MS results and an operational condition used in the GC–MS analysis. A 7820A gas chromatograph coupled with a 5975C network mass spectrometer (GC–MS) (Agilent Technologies, Waldbronn, Germany) was the instrument that analyzed all the samples in this study. An Agilent Technologies HP-5MS 5% Phenyl Methyl Silox column (30 m × 250 μm × 0.25 μm) was the separation column used here. The column temperature was initially set at 80 °C and held for 3 min, then increased at a rate of 5 °C/min up to 280 °C and finally held for 5 min. The total run time was 48 min. The injection volume was 1 µL, with a split ratio of 10:1. Helium was used as the carrier gas at a flow rate of 1 mL/min. MS detection was performed with electron ionization (EI) at 70 eV, operating in the full-scan acquisition mode in the m/z range from 35–350. The authors considered only the chemicals presented with more than 1% of the total detected compounds and a percent matching factor of more than 70% from the database.