A sensitive HPLC method for the determination of fatty acids using 2-(2-(pyren-1-yl)-1Hbenzo[d]imidazol-1-yl) ethyl-p-toluenesulfonate (PBIOTs) as a novel labeling reagent with fluorescencedetection has been developed. PBIOTs could easily and quickly label fatty acids in the presenceof the K2CO3 catalyst at 90C for 30 min in N,N-dimethylformamide solvent. Fatty acids derivativeswere separated on a reversed phase Eclipse XDB-C8 column by HPLC in conjunction with gradientelution. The corresponding derivatives were identified by post-column APCI-MS in positive iondetection mode. PBIOTs-fatty acid derivatives gave an intense molecular ion peak at m=z[MþH]þ; with MS=MS analysis, the collision induced dissociation spectra of m=z [MþH]þproduced the specific fragment ions at m=z [MþH–319]þ and m=z 319.0 (here, m=z 319 is thecore structural moiety of the PBIOTs molecule). The fluorescence excitation and emission wavelengthsof the derivatives were kex¼350 nm and kem¼402 nm, respectively. Linear correlation coefficientsfor all fatty acid derivatives were 0.9985. Detection limits for the labeled fatty acids, at asignal-to-noise ratio of 3:1, were in the range of 10.32– 44.28 fmol. From the extracts of Stellerachamaejasma L, free fatty acids were sensitively determined.
The research has been published on tJournal of Liquid Chromatography & Related Technologies, 33:859–874, 2010
Copyright # Taylor & Francis Group, LLC
ISSN: 1082-6076 print/1520-572X online
DOI: 10.1080/10826071003684620 |
Introduction
