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MB Sample ID: SA191967

Local Sample ID:L#89B_058
Subject ID:SU002125
Subject Type:Mammal
Subject Species:Ovis aries
Taxonomy ID:9940

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Subject:

Subject ID:SU002125
Subject Type:Mammal
Subject Species:Ovis aries
Taxonomy ID:9940

Factors:

Local Sample IDMB Sample IDFactor Level IDLevel ValueFactor Name
L#89B_058SA191967FL023594Control New Borntreatment

Collection:

Collection ID:CO002118
Collection Summary:These samples were flash frozen in liquid nitrogen & stored at -80C
Sample Type:Adipose tissue

Treatment:

Treatment ID:TR002137
Treatment Summary:2, 3-6, Animals were housed at either low or high altitude. Uterine samples are from the adult ewe's while other samples are from either fetus, newborns, or adult animals.

Sample Preparation:

Sampleprep ID:SP002131
Sampleprep Summary:Extraction of Mammalian Tissue Samples: 1. References: Fiehn O, Kind T (2006) Metabolite profiling in blood plasma. In: Metabolomics: Methods and Protocols. Weckwerth W (ed.), Humana Press, Totowa NJ (in press) 2.Starting material: Liver sample: weigh 4mg per sample into 2mL Eppendorf tubes. 3. Equipment: Centrifuge (Eppendorf 5415 D) Calibrated pipettes 1-200μl and 100-1000μl Eppendorf tubes 2mL, clear (Cat. No. 022363204) Centrifuge tubes 50mL, polypropylene Eppendorff Tabletop Centrifuge (Proteomics core Lab.) ThermoElectron Neslab RTE 740 cooling bath at –20°C MiniVortexer (VWR) Orbital Mixing Chilling/Heating Plate (Torrey Pines Scientific Instruments) Speed vacuum concentration system (Labconco Centrivap cold trap) Turex mini homogenizer 4. Chemicals Acetonitrile, LCMS grade (JT Baker; Cat. No.9829-02) Isopropanol, HPLC grade (JT Baker; Cat. No. 9095-02) Methanol Acetone Crushed ice 18 MΩ pure water (Millipore) Nitrogen line with pipette tip pH paper 5-10 (EMD Chem. Inc.) 5. Procedure Preparation of extraction mix and material before experiment: Switch on bath to pre-cool at –20°C (±2°C validity temperature range) Check pH of acetonitrile and isopropanol (pH7) using wetted pH paper Make the extraction solution by mixing acetonitrile, isopropanol and water in proportions 3 : 3 : 2 De-gas the extraction solution for 5 min with nitrogen. Make sure that the nitrogen line was flushed out of air before using it for degassing the extraction solvent solution Sample Preparation Weigh 4mg tissue sample in to a 2mL Eppendorf tube. Add 1mL extraction solvent to the tissue sample and homogenize for 45 seconds ensuring that sample resembles a powder. In between samples, clean the homogenizer in solutions of methanol, acetone, water, and the extraction solvent in the order listed. Vortex samples for 10 seconds, then 5 minutes on 4°C shaker. Centrifuge the samples for 2 minutes at 14,000 rcf. Aliquot 500µL supernatant for analysis, and 500µL for a backup. Store backup aliquots in the -20°C freezer. Evaporate one 500µl analysis aliquot in the Labconco Centrivap cold trap concentrator to complete dryness (typically overnight). The dried aliquot is then re-suspended with 500μl 50% acetonitrile (degassed as given) Centrifuge for 2 minutes at 14,000 rcf using the centrifuge Eppendorf 5415. Remove supernatant to a new Eppendorf tube. Evaporate the supernatant to dryness in the the Labconco Centrivap cold trap concentrator. Submit to derivatization. The residue should contain membrane lipids because these are supposedly not soluble enough to be found in the 50% acetonitrile solution. Therefore, this ‘membrane residue’ is now taken for membrane lipidomic fingerprinting using the nanomate LTQ ion trap mass spectrometer. Likely, a good solvent to redissolve the membrane lipids is e.g. 75% isopropanol (degassed as given above). If the ‘analysis’ aliquot is to be used for semi lipophilic compounds such as tyrosine pathway intermediates (incl. dopamine, serotonine etc, i.e. polar aromatic compounds), then these are supposedly to be found together with the ‘GCTOF’ aliquot. We can assume that this mixture is still too complex for Agilent chipLCMS. Therefore, in order to develop and validate target analysis for such aromatic compounds, we should use some sort of Solid Phase purification. We re-suspend the dried ‘GCTOF’ aliquot in 300 l water (degassed as before) to take out sugars, aliphatic amino acids, hydroxyl acids and similar logP compounds. The residue should contain our target aromatics .We could also try to adjust pH by using low concentration acetate or phosphate buffer. The residue could then be taken up in 50% acetonitrile and used for GCTOF and Agilent chipMS experiments. The other aliquot should be checked how much of our target compounds would actually be found in the ‘sugar’ fraction. 6. Problems To prevent contamination disposable material is used. Control pH from extraction mix. 7. Quality assurance For each sequence of sample extractions, perform one blank negative control extraction by applying the total procedure (i.e. all materials and plastic ware) without biological sample. 8. Disposal of waste Collect all chemicals in appropriate bottles and follow the disposal rules.

Combined analysis:

Analysis ID AN003324
Analysis type MS
Chromatography type GC
Chromatography system Leco Pegasus IV GC
Column Restek Rtx-5Sil (30m x 0.25mm,0.25um)
MS Type EI
MS instrument type QTOF
MS instrument name Leco Pegasus IV TOF
Ion Mode UNSPECIFIED
Units normalized peak height

Chromatography:

Chromatography ID:CH002463
Chromatography Summary:GC-TOF Method: Instruments: Gerstel CIS4 –with dual MPS Injector/ Agilent 6890 GC- Pegasus III TOF MS Injector conditions: Agilent 6890 GC is equipped with a Gerstel automatic liner exchange system (ALEX) that includes a multipurpose sample (MPS2) dual rail, and a Gerstel CIS cold injection system (Gerstel, Muehlheim, Germany) with temperature program as follows: 50°C to 275°C final temperature at a rate of 12 °C/s and hold for 3 minutes. Injection volume is 0.5 μl with 10 μl/s injection speed on a splitless injector with purge time of 25 seconds. Liner (Gerstel #011711-010-00) is changed after every 10 samples, (using the Maestro1 Gerstel software vs. 1.1.4.18). Before and after each injection, the 10 μl injection syringe is washed three times with 10 μl ethyl acetate. Gas Chromatography conditions: A 30 m long, 0.25 mm i.d. Rtx-5Sil MS column (0.25 μm 95% dimethyl 5% diphenyl polysiloxane film) with additional 10 m integrated guard column is used (Restek, Bellefonte PA). 99.9999% pure Helium with built-in purifier (Airgas, Radnor PA) is set at constant flow of 1 ml/min. The oven temperature is held constant at 50°C for 1 min and then ramped at 20°C/min to 330°C at which it is held constant for 5 min.
Instrument Name:Leco Pegasus IV GC
Column Name:Restek Rtx-5Sil (30m x 0.25mm,0.25um)
Chromatography Type:GC

MS:

MS ID:MS003094
Analysis ID:AN003324
Instrument Name:Leco Pegasus IV TOF
Instrument Type:QTOF
MS Type:EI
MS Comments:A Leco Pegasus IV time of flight mass spectrometer is controlled by the Leco ChromaTOF software vs. 2.32 (St. Joseph, MI). The transfer line temperature between gas chromatograph and mass spectrometer is set to 280°C. Electron impact ionization at 70V is employed with an ion source temperature of 250°C. Acquisition rate is 17 spectra/second, with a scan mass range of 85-500 Da.
Ion Mode:UNSPECIFIED
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