Assay development was conducted with samples containing 1 mM 2-allylphenol (Sigma) in DMSO (Sigma) prepared fresh on the same day as GC-FID detection.
An Agilent 7820A gas chromatograph fitted with HP-5 column with the following settings was chosen: FID temp=250C, inlet temp=250C, injection volume=2µL, mode=50:1 split. A limit of detection of 1 µM 2-allylphenol in DMSO was determined by determining the FID response to 6 concentrations of 2-allylphenol: 1 mM, 100 µM, 10 µM, 1 µM, 100 nM, and 0 (DMSO only). All standard curve experiments were performed in triplicate.
Vials containing 500 µL of a solution of 50 mM HEPES buffer, 150 mM NaCl, 2% DMSO, and range of concentrations of 2-allylphenol (1 mM, 500 µM, 250 µM, 125 µM, 0) at pH 7.50 were extracted with 500 µL DMSO, vortexed for 1 sec, and centrifuged for 5 min at 4,700 RPM. An Agilent autosampler was used to inject 2 µL for each run.