Rapid screening of fatty acids using nanostructure-initiator mass spectrometry.

We present the application of nanostructure-initiator mass spectrometry (NIMS) as a fast and simple method for the analysis of plant and microbial fatty acids. NIMS allowed the direct detection of a broad range of saturated and unsaturated fatty acids in negative mode showing linearity over several orders of magnitude with a limit of detection at the femtomole level. Additionally, the fatty acid compositions of olive and soybean oil and the algal species Chlamydomonas reinhardtii could be determined both qualitatively and quantitatively with only minimal sample volumes and preparation steps. The unique properties of the NIMS surface allowed for an in situ sample cleanup step leading to a more than 10-fold increase of the signal-to-noise ratio. Our data provide the basis for rapid screening of plant and microbial oils and may aid in the development of biodiesel fuels.