Agilent 6890n gc fid

The free amino acid of T65 crude product was determined by the GC-FID (gas chromatography–flame ionization detector) method at the Korea Polymer Testing and Research Institute (Koptri). For the GC-FID method, the machine used was an Agilent 6890N GC-FID; column, ZB-AAA (10 m × 0.25 mm); injection part temperature, 250 °C; injection column, 2 μL; split ratio, 5:1; temperature condition, 110 °C → 32 °C/min → 320 °C; detector, FID @ 320 °C; carrier, nitrogen gas, 1.5 mL/min; maker, Phenomenex; amino acid standard; and concentration, 200 μmol/L.
The composite amino acids of T65 crude product was determined by the GC-FID (gas chromatography–flame ionization detector) method at the Korea Polymer Testing and Research Institute (Koptri). For GC-FID, the machine used was an Agilent 6890N GC-FID; column, ZB-AAA (10 m × 0.25 mm); injection part temperature, 250 °C; injection column, 2 μL; split ratio, 5:1; temperature condition, 110 °C → 32 °C/min → 320 °C; detector, FID @ 320 °C; carrier, nitrogen gas, 1.5 mL/min; maker, Phenomenex; amino acid standard; and concentration, 200 μmol/L.

SST estimates are based on the reconstruction of the U^K′₃₇ index from lithified marine sequences (Cleaveland and Herbert, 2009; Beltran et al., 2011 ). Samples were homogenized using a mortar and pestle. Lipid extractions were done on a Dionex 200 Accelerated Solvent Extractor. Total lipid extract was obtained from ~ 10 g of sediment using 9:1 DCM:MeOH. Samples underwent silica gel separation prior to gas chromatographic analysis to ensure reliable alkenone quantification and minimize system drift. Alkenone concentrations were quantified on an Agilent 6890N GC-FID and SST calculated following the Prahl and Wakeham (1987) calibration of the U^K'₃₇ index. Drift and error were monitored by including sample replicates and a lab standard every 12 samples. The analytical error of the laboratory as determined by replicates is 0.2 °C.
In previous EOC studies, climatic conditions have been described in qualitative terms, e.g. temperate and subtropical. We assign the following SST ranges to the respective qualitative terms (Karami et al., 2011 ): temperate = 15–17 °C; warm temperate = 17–21 °C; subtropical = 21–25 °C; tropical = > 25 °C.

The analyses were carried out with an Agilent 6890N GC-FID (Santa Clara, CA, USA) system equipped with a TR-WAX (Thermo Fisher Scientific, Waltham, MA, USA) capillary column (30 m × 250 µm × 1.0 µm). The GC oven temperature was programmed to increase from 60 (5 min isothermal) to 240 °C at 30 °C/min (5 min isothermal). High-purity hydrogen (5.0) was used as a carrier gas at 2.9 mL/min (29 cm/s) in constant pressure mode. Vials were crimped in order to minimize the loss of volatile species. Absolute ethanol (a.r., Molar Chemicals Kft., Halásztelek, Hungary) was used as a standard to identify the ethanol peak based on retention time. For FID quantification, external standard technique was used. Then, 100 mg Absolute ethanol was diluted with dimethyl sulfoxide (a.r., Molar Chemicals Kft., Halásztelek, Hungary) to achieve a final concentration of 10 mg/mL as a stock solution. The calibration curve covered the range 0.5 to 2.0 mg/mL.