title: Quantitative evaluation of carbon isotopic fractionation during reversed-phase high-performance liquid chromatography.
abstract: The fractionation of 13C during low-performance preparative LC and high-performance LC is reported quantitatively for methyl palmitate and using high-precision isotope ratio mass spectrometry (IR-MS). For both preparative and high-performance analytical columns, 13C enrichment is about 7% greater than the parent starting material, drops sharply in the first section of the peak and then settles to a value about 1% below that of the starting material. Recycling over a single HPLC column did not induce greater fractionation. These results emphasize the importance of quantitative peak collection for high-precision IR-MS studies, particularly the first part of the peak where the isotope ratio changes rapidly.
authors.affiliation: Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853-1301, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Caimi
authors.forename: J T
authors.initials: JT
authors.lastname: Brenna
mesh_terms: D002247:Carbon Isotopes; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D010168:Palmitates / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002247:Carbon Isotopes; D010168:Palmitates; C019012:methyl palmitate