Development of a chromatography free method based on DART-Triple Quadrupole mass spectrometry for targeting adulterants in saffron

Direct analysis in real time-mass spectrometry (DART-MS) is a rapid and accurate analytical technique that does not require extensive sample preparation and has been exploited in food analysis and in forensics. Saffron is a valuable spice derived from Crocus sativus stigmas and due to the high costs has been the main target of many fraudulent actions. Despite the traditional methods requiring complex and long protocols, new robust and fast methods are urgently demanded to be able detect tiny amounts of adulterants in saffron at levels lower than 20% reached by the conventional methodologies. In this note we describe the development of a fast, robust, and high throughput screening method for safflower and turmeric detection as adulterants in safflower. The study explores the potential of DART combined with targeted Multiple Reaction Monitoring (MRM) on a DART-EVOQ triple quadrupole mass spectrometer for the detection and quantification of safflower and turmeric in saffron at the lowest level of 5%. Full scan and Product Ion Scan experiments allowed to identify potential markers and after selection of the best transitions for each marker, MRM experiments were carried out in order to perform quantitative analysis. Adding caffeine as an internal standard proved to improve calibration linearity and reduce measurement variability. Specific markers along with their main fragments for safflower and turmeric were confirmed as suitable markers for detecting adulteration of these low-value spices in saffron and calibration curves showed a strong correlation. Summarizing a quick and solvent free method based on DART – Mass Spectrometry method was developed on the new EVOQ triple Quadrupole mass spectrometer, demonstrating to be a promising method for detecting tiny amounts of adulterants like safflower and turmeric in saffron through the detection of two markers and their respective transitions.