GNPS_GC_NYC_fecal samples_SCFAs_MCFAs_SPME
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Agilent 7200 GC-MS qToF
ORGANISM(S): Homo Sapiens (ncbitaxon:9606)
SUBMITTER: 
Pieter Dorrestein
PROVIDER: MSV000084277 | GNPS |
REPOSITORIES: GNPS
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All of the sampling has been conducted under UC San Diego IRB 171662. Cleaned and degassed PDMS patches have been placed on skin of a volunteer overnight and secured in place with waterproof bandage. After sampling, the bandage was removed, patches placed into 2 mL borosilicate vials using clean tweezers and capped with a crimp camp with silicone septum. The GC-MS analysis was carried out using the Agilent 7200 GC/QTOF equipped with robotic sampler system.
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Project description:All of the sampling has been conducted under UC San Diego IRB #171662. Cleaned and degassed PDMS patches have been placed on skin of a volunteer overnight and secured in place with waterproof bandage. After sampling, the bandage was removed, patches placed into 2 mL borosilicate vials using clean tweezers and 150 uL of HPLC grade methanol added for extraction. The extraction was carried out overnight at room temperature. After extraction, the sample was transferred into a 200 uL insert in a 2 mL vial and the vial capped with a crimp camp with silicone septum. The GC-MS analysis was carried out using the Agilent 7200 GC/QTOF equipped with robotic sampler system.
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The data for medium chain fatty acids:
Post-thawing, human fecal (50 mg) were sequentially extracted using solvent extraction with 100 uL 100% Methanol HPLC grade followed by sonication for 10 minutes and centrifugation (12000 rpm, 5 minutes). Supernatant was then transferred to a new 1.7 ml tube and the samples were lyophilized followed by resuspension in 50 uL MTBSTFA (N-tert-Butyldimethylsilyl-N-methyltrifluoroacetamide with 1% tert-Butyldimethylchlorosilane). After sonication (5 minutes) and centrifugation (12000 rpm, 10 minutes) the prepared samples were placed in a 200 uL insert in 2 ml borosilicate vials and capped with a screw cap with silicone septum. The samples were stored at -20 C and thawed immediately prior to analysis.
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The GC-MS analysis was carried out using the Agilent 7200 GC/QTOF equipped with robotic sampler system.
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