GNPS-GC Earth Microbiome Project EMP Soil and Fecal Samples - GC-MS Silylated Sample Preparation

GNPS-GC Earth Microbiome Project EMP Soil and Fecal Samples ran on GC-MS (EI) after Silylation. Provided by Sneha Couvillion, Thomas Metz at the PNNL.

See http://www.earthmicrobiome.org/protocols-and-standards/ for more details on the protocol.

About the mass spectrometry method: An Agilent 7890A gas chromatograph coupled with a single quadrupole 5975C mass spectrometer (Agilent Technologies, Inc.) was used for all analyses. A HP-5MS column (30 m × 0.25 mm × 0.25 ?m; Agilent Technologies) was used for untargeted analyses. Samples (1 uL) were injected in splitless mode, and the helium gas flow rate was determined by the Agilent Retention Time Locking function based on analysis of deuterated myristic acid (Agilent Technologies, Santa Clara, CA). The injection port temperature was held at 250°C throughout the analysis. The GC oven was held at 60°C for 1 min after injection, and the temperature was then increased to 325°C by 10°C/min, followed by a 5 min hold at 325°C. Data were collected over the mass range 50–550 m/z. A mixture of FAMEs (C8–C28) was analyzed together with the samples for retention index alignment purposes during subsequent data analysis.

Every batch of samples that are run on the GCMS have accompanying blanks and a FAMES file.