Automated sample preparation and fast GC-MS determination of fatty acids in blood samples and dietary supplements

Abstract

The present research is focused on the optimization of an automatized sample preparation and fast gas chromatography-mass spectrometry (GC-MS) method for the analysis of fatty acid methyl esters (FAMEs) in blood samples and dietary supplements, with the primary objective being a significant reduction of the analysis time and, hence, an enhanced sample throughput. The mass spectrometer was operated in the scan/selected ion monitoring (SIM) acquisition method, thus enabling the obtainment of qualitative and (highly sensitive) quantitative data. The separation of FAMEs was obtained in about 11 min by using a micro-bore column of dimensions 15 m × 0.10 mm ID × 0.10 µm d_f with a polyethylene glycol stationary phase. The novelty of the research involves reducing analysis time by using the novel fast GC-MS method with increased identification reliability and sensitivity in a single chromatographic run. With regard to the figures of merit, linearity, accuracy, and limits of detection (LoD) and quantification (LoQ) were determined. Specifically, regression coefficients were between 0.9901 and 0.9996; the LoDs ranged from 0.05 to 1.02 µg g^-1 for the blood analysis method, and from 0.05 to 0.26 mg g^-1 in the case of the dietary supplement approach. With respect to LoQs, the values were in the ranges of 0.15-3.39 µg g^-1 and 0.15-0.86 mg g^-1 for blood and dietary supplements analysis methods, respectively. Accuracy was evaluated by analyzing certified reference materials (human plasma, fish oil).

Keywords: Dried blood spot; Fast GC–MS; Fatty acid methyl esters; Lipidomics; Scan/SIM acquisition; Selected ion monitoring.