Tyrosol and Hydroxytyrosol Determination in Extra Virgin Olive Oil with Direct Liquid Electron Ionization-Tandem Mass Spectrometry

Extra virgin olive oil (EVOO) is one of the main ingredients Mediterranean diet. It claimed as a functional food for its unique content health-promoting compounds. Tyrosol (Tyr), Hydroxytyrosol (Htyr), and their phenolic derivatives present in EVOO show beneficial properties, identification quantification, both free form after hydrolysis more complex precursors, are important to certify quality. An alternative method quantifying total Tyr Htyr presented using an LC–MS interface based on electron ionization (EI), called liquid (LEI). This requires neither sample preparation nor chromatography; diluted injected. The selectivity sensitivity were assessed multiple reaction monitoring mode (MRM), obtaining confirmation quantification actual samples ranging from 5 11 mg/Kg forms 32 80 amount hydrolysis. Two MS/MS transitions acquired compounds Q/q ratios confirmatory parameters. Standard addition calibration curves demonstrated optimal linearity negligible matrix effects, allowing correct even without expensive difficult find labeled internal standards. After several weeks operation, system’s repeatability was excellent, with intraday RSD (%) spanning five nine interday 9 11.