Acetate, propionate and butyrate in plasma: determination of the concentration and isotopic enrichment by gas chromatography/mass spectrometry with positive chemical ionization.
This study describes a rapid and simple method to determine short-chain fatty acid (SCFA) concentrations and their isotopic enrichments (M(0) + 1 and M(0) + 2) in human plasma. Sample preparation involves SCFA extraction and derivatization with 1-(tert-butyldimethylsilyl)imidazole. Gas chromatography/mass spectrometry was performed using chemical ionization with ammonia as the reagent gas. Outstanding resolution, excellent linearity and good detection limits were obtained. Inter-assay and intra-assay repeatability was below 10% and 3% respectively for SCFA concentration. Inter-assay repeatability was below 5%, 4%, 6%, and 14% for isotopic enrichment determination of [1-(13)C]acetate and [1,2-(13)C(2)]acetate, [1-(13)C]propionate and [1-(13)C]butyrate respectively, with intra-assay being below 6%. Such SCFA concentrations and isotopic enrichments were determined in the plasma of rats infused with a (13)C-labeled SCFA. The turnovers of acetate, propionate and butyrate in rats were 19 micromol kg(-1) min(-1), 2.6 micromol kg(-1) min(-1), 0.3 micromol kg(-1) min(-1) respectively.
Pouteau
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Nestlé Research Centre, Nestec Ltd, Vers-chez-les-Blanc, PO Box 44, 1000 Lausanne 26, Switzerland. etienne.pouteau@rdls.nestle.com
Meirim
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Métairon
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Fay
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LB
D000085:Acetates / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D000818:Animals; D002087:Butyrates / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D002247:Carbon Isotopes; D005215:Fasting; D005232:Fatty Acids, Volatile / Q000097:blood; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D011422:Propionates / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D000085:Acetates; D002087:Butyrates; D002247:Carbon Isotopes; D005232:Fatty Acids, Volatile; D011422:Propionates; C029658:propionic acid