Direct 1H NMR Quantitation of Valuable Furan Fatty Acids in Fish Oils and Fish Oil Fractions.
Vera GottsteinMarco MüllerJohannes GüntherThomas KuballaWalter VetterPublished in: Journal of agricultural and food chemistry (2019)
Furan fatty acids (FuFAs) are a class of naturally occurring minor fatty acids with fish as the richest food source. Typically, FuFA analysis is cumbersome and involves several steps. We developed a quantitative 1H NMR method (qNMR) in which fish oil samples were directly measured after dilution with CDCl3 stabilized with silver (which was essential to prevent formation of radicals) and addition of an internal standard. The singlet at δ = 1.89 ppm was suitable for quantitation of monomethyl FuFAs, whereas the signal at δ = 1.83 ppm was suitable to quantitate dimethyl FuFAs. Using standard NMR tubes with 650 μL solvent, the limit of quantitation was 0.5 μg (dimethyl FuFAs) and 1.0 μg (monomethyl FuFAs). Applied to three fish oil and two enriched fish oil samples (sample weight, 10 mg), the final qNMR method resulted in similar total FuFA contents as determined in parallel by gas chromatography coupled to mass spectrometry.
Keyphrases
- fatty acid
- mass spectrometry
- gas chromatography
- high resolution
- liquid chromatography
- tandem mass spectrometry
- ms ms
- high performance liquid chromatography
- magnetic resonance
- liquid chromatography tandem mass spectrometry
- solid phase extraction
- high resolution mass spectrometry
- capillary electrophoresis
- solid state
- physical activity
- body mass index
- gas chromatography mass spectrometry
- simultaneous determination
- weight gain
- risk assessment
- quantum dots
- ionic liquid