title: Positive-ion thermospray liquid chromatography-mass spectrometry: detection of organic acidurias.
abstract: Positive-ion thermospray liquid chromatography-mass spectrometry (TSP-LC-MS) is used to detect organic acids via the direct injection of untreated urine from newborns and infants. Two methods are reported for the separation of organic acids. The separation of urinary organic acids is effected in either an acidic, pH 2.5 sulfuric acid, or a non-acidic, 0.05 M ammonium acetate, pH 6.8, mobile phase. Use of pH 2.5 sulfuric acid and an HPX-87H organic acid column produces better separation but has less sensitivity than the use of 0.05 M ammonium acetate, pH 6.8 and a C18 column. Positive ion TSP-LC-MS has been used to detect methylmalonic aciduria, 3-hydroxy-3-methylglutaric aciduria, propionic aciduria, isovaleric aciduria and argininosuccinic aciduria.
authors.affiliation: Department of Pediatrics, University of Michigan, Ann Arbor 48109.
authors.forename: D N
authors.initials: DN
authors.lastname: Buchanan
authors.forename: J
authors.initials: J
authors.lastname: Muenzer
authors.forename: J G
authors.initials: JG
authors.lastname: Thoene
mesh_terms: D001125:Argininosuccinic Acid / Q000652:urine; D002264:Carboxylic Acids / Q000652:urine*; D002855:Chromatography, Thin Layer / Q000379:methods*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D015093:Meglutol / Q000652:urine; D008661:Metabolism, Inborn Errors / Q000652:urine*; D008764:Methylmalonic Acid / Q000652:urine; D012680:Sensitivity and Specificity; D014631:Valerates / Q000652:urine
chemical_list: D002264:Carboxylic Acids; D014631:Valerates; D001125:Argininosuccinic Acid; C004961:beta-hydroxyisovaleric acid; D008764:Methylmalonic Acid; D015093:Meglutol