| Summary: | Here we present concentration and mass accumulation rate of C37 alkenones in discrete samples from ODP site 883. Approximately 1–4 g of sediment was freeze-dried and homogenized prior to extraction with a Dionex 200 Accelerated Solvent Extractor using 100% dichloromethane. Prior to quantification, the total lipid extract was evaporated under N2 and redissolved in 200 μL toluene spiked with n-hexatriacontane (C36) and n-heptatriacontane (C37) standards. Alkenone concentrations were calculated by comparison of C37:2 and C37:3 alkenone peak areas to the peak areas of the C36 and C37 internal standards determined by an Agilent Technologies 6890 gas chromatograph flame ionization detector (GC-FID), with an Agilent Technologies DB-1 column (60 m, 0.32 mm diameter, 0.10 mm film thickness). 1 μL of total lipid extract was injected at an initial temperature of 90°C, increasing to 255°C at 40°C/min, then to 300°C at 1°C/min, ramping to 320°C at 10°C/min, and ending with an isothermal hold at 320°C for 11 minutes. 228 of 504 samples were analyzed at least in duplicate, yielding a mean standard deviation of 0.017 pmol•mg-1 or 9.2 ng*g-1.
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