7820a gc ms system

General Methods. Melting points were measured in KRUSS melting point meter using open capillary tubes and are uncorrected. ¹H and ¹³C NMR spectra were recorded on a Bruker 300 MHz instrument in DMSO using TMS as internal standard. Standard Bruker software was used throughout. Chemical shifts are given in parts per million (δ-scale) and the coupling constants are given in Hertz. IR spectra were recorded in a Perkin Elmer system 2000 FT IR instrument (KBr). Elemental analyses were performed on a Perkin Elmer 2400 Series II Elemental CHNS analyser. Mass spectra were recorded in Agilent technologies 7820A GC-MS system.

Amino acid metabolites, GABA, serotonin, and dopamine were quantified using GC coupled with Mass Spectrometry detection (GC-MS). The samples were derivatized with an EZ-faast kit from Phenomenex (Torrance, CA, USA) as per standard protocol using 100 µL of the centrifuged and filtered supernatant. Norvaline (0.2 mM) was used as an internal standard. 1 µL of the derivatized sample was injected onto a 7820A GC-MS system equipped with a DB-1 column (30 m × 0.320 mm × 0.50 µm) both from Agilent Technologies, Inc. (Mississauga, ON, Canada) through a temperature gradient from 80 °C to 300 °C at a rate of 20 °C/min. The compounds were identified and quantified with the amino acid standards provided with the EZ-faast kit. Results are presented as mean ± SEM of four biological replicates.