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MB Sample ID: SA121498
Local Sample ID: | SCFA_S85 |
Subject ID: | SU001505 |
Subject Type: | Human |
Subject Species: | Homo sapiens |
Taxonomy ID: | 9606 |
Select appropriate tab below to view additional metadata details:
Subject:
Subject ID: | SU001505 |
Subject Type: | Human |
Subject Species: | Homo sapiens |
Taxonomy ID: | 9606 |
Factors:
Local Sample ID | MB Sample ID | Factor Level ID | Level Value | Factor Name |
---|---|---|---|---|
SCFA_S85 | SA121498 | FL014890 | Control | Treatment |
Collection:
Collection ID: | CO001500 |
Collection Summary: | Stool samples were collected by the parents using sterile faeces containers and stored at -20oC at home. Samples were then transported to the lab in cold chain within 20 hours of sample collection for processing. After processing, sample were stored at -80oC until further analysis. |
Sample Type: | Feces |
Storage Conditions: | -80℃ |
Treatment:
Treatment ID: | TR001520 |
Treatment Summary: | Control vs Eczema (Non-allergen sensitized atopic eczema, Allergen-sensitiized atopic eczema) |
Sample Preparation:
Sampleprep ID: | SP001513 |
Sampleprep Summary: | 500 L of ice-cold extraction solvent (1:1 v/v ACN/water) containing 10 M of d5-benzoic acid as internal standard (IS) was added to 250 mg of wet stool sample and subjected to vortex mixing for 5 min at ambient temperature (24 ± 1 ◦C). The ratio of extraction solvent to wet sample weight was kept constant (2 L:1 mg) to prevent variable extraction efficiencies. The suspension was then centrifuged at 18 000g for 10 min at 4 ◦C. The supernatant was carefully removed and centrifuged again at 18 000g for 10 min at 4 ◦C. An aliquot of 100 L was subsequently derivatized using a final concentration of 10 mM aniline and 5 mM EDC for 2 h at 4 ◦C. The derivatization reaction was quenched using a final concentration of 18 mM succinic acid and 4.6 mM 2-mercaptoethanol for 2 h at 4 ◦C. An aliquot of each sample was further diluted 100-fold. All samples were stored at 4 ◦C until analysis on the same day |
Combined analysis:
Analysis ID | AN002393 |
---|---|
Analysis type | MS |
Chromatography type | Reversed phase |
Chromatography system | Agilent 1290 Infinity |
Column | Waters Acquity BEH HSS T3 (100 x 2.1mm,1.8um) |
MS Type | ESI |
MS instrument type | Triple quadrupole |
MS instrument name | ABI Sciex 5500 QTrap |
Ion Mode | POSITIVE |
Units | nM |
Chromatography:
Chromatography ID: | CH001759 |
Chromatography Summary: | Water and HPLC-grade isopropanol, both acidified with 0.1% formic acid were used as mobile phases A and B respectively. Chromatographic separation was achieved using an Acquity UPLC HSS T3 1.8 M, 2.1 mm x 100 mm column at a flow rate of 0.35 mL/min under the following condition: isocratic 15% B (0.00 − 2.00 min), linear gradient 15% to 33% B (2.01–6.00 min), linear gradient 33% to 34% B (6.01–7.50 min), linear gradient 34% to 36% B (7.51–12.00 min), isocratic 100% B (12.01–13.00 min), isocratic 15% B (13.01–15.00 min). Using an autosampler thermostatted at 4 ◦C, 1 L of each sample was injected onto the column maintained at 50 ◦C. The needle was flushed with methanol postinjection to minimize carry-over effect. |
Instrument Name: | Agilent 1290 Infinity |
Column Name: | Waters Acquity BEH HSS T3 (100 x 2.1mm,1.8um) |
Flow Gradient: | isocratic 15% B (0.00 - 2.00 min), linear gradient 15% to 33% B (2.01-6.00 min), linear gradient 33% to 34% B (6.01-7.50 min), linear gradient 34% to 36% B (7.51-12.00 min), isocratic 100% B (12.01-13.00 min), isocratic 15% B (13.01-15.00 min). |
Flow Rate: | 0.35 mL/min |
Solvent A: | 100% water; 0.1% formic acid |
Solvent B: | 100% isopropanol; 0.1% formic acid |
Chromatography Type: | Reversed phase |
MS:
MS ID: | MS002235 |
Analysis ID: | AN002393 |
Instrument Name: | ABI Sciex 5500 QTrap |
Instrument Type: | Triple quadrupole |
MS Type: | ESI |
MS Comments: | ion spray voltage, 5500 V; temperature, 500 ◦C; curtain gas, 20 psi; ion source gas 1, 18 psi; and ion source gas 2, 18 psi. Data were acquired in scheduled MRM mode using a 30 s detection window. More details available at Chan, J. C.; Kioh, D. Y.; Yap, G. C.; Lee, B. W.; Chan, E. C., A novel LCMSMS method for quantitative measurement of short-chain fatty acids in human stool derivatized with (12)C- and (13)C-labelled aniline. Journal of pharmaceutical and biomedical analysis 2017, 138, 43-53. |
Ion Mode: | POSITIVE |