Agilent 5977a mass spectrometer detector system

Gas chromatography-mass spectrometry (GC-MS) analysis of the essential oil was performed on an Agilent 7890B Gas Chromatography system (Agilent Technologies, USA) coupled to an Agilent 5977A Mass Spectrometer Detector system (Agilent Technologies). The HP5-MS type capillary column (a non-polar column; 30 m x 0.25 mm id and 0.25 µm film thickness, Agilent Technologies) was employed to separate and analyze individual constituents. Then, 1 µl of diluted sample (1/100; v/v, essential oil in acetone) was injected into the split mode with a 1:20 split ratio. The gas chromatographic conditions were carrier gas helium (1.0 mL/min), initial oven temperature 40 °C for 3 min isothermal, 40 to 150 °C at a rate of 6 °C/min, and 150 to 320 °C at a rate of 10 °C/min, and then held for 3 min. The injector temperature was set to 270 °C. Mass spectra were scanned in the range 40 to 500 amu with EI mode (70 eV) in full scan mode. The percentage composition of essential oil was calculated using the peak normalization method. The essential oil constituents were identified by comparing their retention indices (RI), mass spectra with NIST (National Institute of Standards and Technology), Adams library spectra, Wiley 7 n.1 mass computer library, and in published literature [30 ,31 (link)].

A gas chromatographic-mass spectrometric (GC-MS) analysis of the EO was performed on an Agilent 7890B Gas Chromatography system (Agilent Technologies, Wilmington, NC, USA), coupled to an Agilent 5977A Mass Spectrometer Detector system (Agilent Technologies, Wilmington, USA).