J w dbffap fused silica capillary column

Cells transfected with siRNA (as well as corresponding controls) were trypsinized for 5min, collected and spun at 1200rpm for 5min to pellet hepatocytes. HepG2 cell pellets were washed in 1x PBS. Lipid extractions were conducted using previously described protocols [44, 45] . Samples were analyzed using a 7890B gas chromatography system (Agilent Technologies) with a flame ionization detector, and samples were separated on a J&W DBFFAP fused-silica capillary column (15m, 0.1µm film thickness, 0.1mm i.d.;
Agilent Technologies). Fatty acid peaks were identified by comparison with retention times of fatty acid methyl ester standards. To estimate SCD1 activity, we calculated the product-to-precursor fatty acid ratio (i.e., 18:1n9/18:0 and 16:1n7/16:0), as previously reported [46, 47] . Fatty acid data were normalized to protein concentrations for each treatment condition and reported as µg fatty acid per µg/µl protein.

Analyses were conducted according to Standard Methods (APHA et al. 1998) . Volatile fatty acids were determined using an Agilent 6890 N gas chromatograph equipped with a flame ionization detector (FID) (T = 250 °C). Samples were analysed through an Agilent J&W DB-FFAP fused silica capillary column (15 m length, 0.53 mm i.D. Â 0.5 mm film) using hydrogen as carrier. The inlet was working in split mode, with a split ratio of 20:1. The instrument was programmed with a ramp temperature from 80 °C to 100 °C (10 °C/min). Before GC analyses, samples were centrifuged at 4,500 rpm for five minutes and the supernatant was filtered at 0.2 mm using acetate cellulose syringe filters (Whatman).