title: Improved LC-MS method for the determination of fatty acids in red blood cells by LC-orbitrap MS.
abstract: We report a new method for fast and sensitive analyses of biologically relevant fatty acids (FAs) in red blood cells (RBC) by liquid chromatography mass spectrometry (LC-MS). A new chemical derivatization approach was developed forming picolylamides from FAs in a quantitative reaction. Fourteen derivatized FA standards, including saturated and unsaturated FAs from C14 to C22, were efficiently separated within 15 min. In addition, the use of a recently introduced benchtop orbitrap mass spectrometer under positive electrospray ionization (ESI) full scan mode showed a 2-10-fold improvement in sensitivity compared with a conventional tandem MS method, with a limit of detection in the low femtomole range for saturated and unsaturated FAs. The developed method was applied to determine FA concentrations in RBC with intra- and interday coefficients of variation below 10%.
authors.affiliation: Cancer Research Center of Hawaii, 1236 Lauhala Street, Honolulu, Hawaii 96813, USA.
authors.forename: Xingnan
authors.initials: X
authors.lastname: Li
authors.forename: Adrian A
authors.initials: AA
authors.lastname: Franke
mesh_terms: D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004912:Erythrocytes / Q000737:chemistry*; D005227:Fatty Acids / Q000032:analysis*; D006801:Humans; D015394:Molecular Structure; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013237:Stereoisomerism
chemical_list: D000577:Amides; D005227:Fatty Acids