7890a 5975c gc msd system

The GC-MS analysis of EOVJRR was performed with fused silica capillary column samples that were injected into a 7890A/5975C-GC/MSD system (Agilent, USA) with ChemStation workstation and NIST mass spectrometry database. The chromatographic separation was performed using a DB-5MS gas chromatography column (30 m × 250 μm × 0.25 μm, Agilent, USA). The temperature of the oven program was firstly raised to 40°C and maintained for 5 min, and then temperature was increased from 40°C to 280°C at a rate of 5°C/min and that temperature was maintained for 5 min. Helium was used as carrier gas at a constant flow rate of 1.0 mL/min. EI mode at 70 eV was used as the ionization mode of the spectrometers with a source temperature of 230°C. The split ratio was 40 : 1; the mass spectra plot was obtained with a scan range from 20 to 450 m/z. The components were identified by comparing their mass spectra with data from NIST (National Institute of Standards and Technology, US). The sample injection volume is 1.0 μL.

To get the high-quality data in high throughput analysis, the quality control (QC) method was used to monitor analytical accuracy from the pooled samples and report the data quality as previously described^{69 (link)}. The pooled mixtures were prepared by 20 μl of all the biological test samples.
The samples were analyzed by Agilent 7890A/5975C GC/MSD System. The complex mixture of compounds was separated on GC column HP-5MS (30 m × 250 μm × 0.25 μm, Agilent) coated with 5% phenyl/95% methylpolysiloxane. To separate the derivatives, the helium was the carrier gas set at a constant flow of 1 ml/min. 1 µl sample was injected by a split mode with a split ratio of 20:1 using the auto-sampler. The injection port temperature was set at 280 °C, the transfer line temperature set to 150 °C and the ion source temperature adjusted to 230 °C. The programs of temperature-rise were as followed: 60 °C initially for 2 min, increased to 300 °C at 10 °C/min and 300 °C was maintained for 5 min. The range of mass spectrometry was set from 35 to 750 (m/z) by a full-scan method.