Thermo dsq mass spectrometer

For GC–MS analysis, the Thermo Trace Ultra chromatograph was used, coupled with the Thermo DSQ mass spectrometer (Thermo Scientific, Warsaw, Poland). The analyses were carried out using the Rxi^®-5Sil MS column (30 m × 0.25 mm i.d., 0.25 μm film thickness; Restek, Bellefonte, PA, USA). The following working parameters were employed: injector temperature, 260 °C; oven temperatures, 100 °C for 2 min, ramp at 20 °C/min to 260 °C; carrier gas (helium) flow rate, 1.2 mL min⁻¹; MS transfer line temperature, 250 °C; MS source temperature, 250 °C; injection volume, 1 μL in the splitless mode. For structural confirmation, electron ionization (EI) mass spectra were matched to an EI-MS library [21 ].

Geraniol, geraniol derivatives and other volatiles were extracted and analyzed by headspace solid-phase microextraction (HS-SPME) using poly(dimethylsiloxane) (PDMS) fibers (Supelco, USA) coupled to gas chromatography (GC) and GC–mass spectrometry (MS) as previously reported [17 (link)]. 2-Octanol (0.2 μg) was used as internal control. Identification of compounds was determined by comparing retention times and mass spectra with those of standards using a Thermo-Scientific model Focus-GC equipped with a HP-Innowax column (length 30 m; inside diameter 0.25 mm; film thickness 0.25 μm) and a Thermo Trace GC Ultra gas chromatograph coupled to a Thermo DSQ mass spectrometer (Thermo-Scientific), under the same chromatographic conditions. Ion spectra of the peaks of interest were identified by comparison with computerized libraries (e.g. Wiley6, NIST). The oven temperature was programmed as follows: 60°C for 5 min, raised to 190°C at 5°C/min, then raised to 250°C at 20°C/min and held 2 min at 250°C. The injector temperature was 220°C. Helium was the carrier gas at 1 mL/min in the splitless mode. Compounds were quantified by integrating the peak areas of GC chromatograms.

For GC–MS analysis, the Thermo Trace Ultra chromatograph was used, coupled with the Thermo DSQ mass spectrometer (Thermo Scientific). The analyses were carried out with use of the Rxi^®-5Sil MS column (Restek, Bellefonte, PA, USA). The following working parameters were employed: injector temperature, 260 °C; oven temperatures, 100 °C for 2 min, ramp at 20 °C min⁻¹ to 260 °C; carrier gas (helium) flow rate, 1.2 mL min⁻¹; MS transfer line temperature, 250 °C; MS source temperature, 250 °C; injection volume, 1 μL, on splitless mode.
The obtained electron ionization (EI) mass spectra were compared to those of an EI-MS library [28 ] for structural confirmation.