title: Online stable carbon isotope ratio measurement in formic acid, acetic acid, methanol and ethanol in water by high performance liquid chromatography-isotope ratio mass spectrometry.
abstract: A suitable analysis condition was determined for high performance liquid chromatography-isotope ratio mass spectrometry (HPLC-IRMS) while making sequential measurements of stable carbon isotope ratios of delta(13)C in formic acid, acetic acid, methanol and ethanol dissolved in water. For this online column separation method, organic reagents are not applicable due to carbon contamination; thus, water and KH(2)PO(4) at low concentrations were tested as mobile phase in combination with a HyPURITY AQUASTAR column. Formic acid, acetic acid, methanol and ethanol were separated when 2 mM KH(2)PO(4) aqueous solution was used. Under the determined analysis condition for HPLC-IRMS, carbon concentrations could be measured quantitatively as well as carbon isotope ratio when carbon concentration was higher than 0.4 mM L for each chemical.
authors.affiliation: National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555, Japan. k tagami@nirs.go.jp
authors.forename: Keiko
authors.initials: K
authors.lastname: Tagami
authors.forename: Shigeo
authors.initials: S
authors.lastname: Uchida
mesh_terms: D019342:Acetic Acid / Q000032:analysis*; D002247:Carbon Isotopes; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods; D000431:Ethanol / Q000032:analysis*; D005561:Formates / Q000032:analysis*; D013058:Mass Spectrometry / Q000295:instrumentation* / Q000379:methods*; D000432:Methanol / Q000032:analysis*; D010710:Phosphates / Q000737:chemistry; D017680:Potassium Compounds / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D005561:Formates; D010710:Phosphates; D017680:Potassium Compounds; D014867:Water; C030544:formic acid; D000431:Ethanol; C013216:potassium phosphate; D019342:Acetic Acid; D000432:Methanol