DEVELOPMENT OF A NOVEL UHPLC-MS/MS METHOD FOR THE DETERMINATION OF OCHRATOXIN A IN TEA.

CINA, MARIEL; CERUTTI, SOLEDAD

Workshop; Green Chemistry Postgraduate Summer School; 2021

Abstract Tea is a traditional beverage widely consumed worlwide [1]. Approximately, because the annual increase in its consumption, near 7 million tons will be produced in 2023. Tea may contain different families of compounds associated to promote human health wellness. However, numerous publications show that also chemical contaminants and natural toxins produced by filamentous fungi (mycotoxins) can be found. Mycotoxins have been detected in different tea varieties (black, red, green), like aflatoxins, ochratoxin A (OTA), and fumonisins [2]. OTA is responsible for producing many effects on human and animal health, such as nephrotoxic, teratogenic, immunosuppressive, embryotoxic, genotoxic, and mutagenic effects. Hence, the European Commission Regulation (EC) 1881/2006 [3] has established maximum levels (MLs) of OTA in foods and feed products (e.g., a 5 ug kg- 1 MLs has been set for roasted coffee), but no European regulation for mycotoxins in tea samples has been reported yet [4]. In addition, to make compatible detection and regulation limits for mycotoxins analysis, robust and sensitive analytical methods are required. These objectives are attainable only if cutting-edge technology (UHPLC-MS/MS, among others) is applied. The development of sensitive, accurate, low-cost, quick, and eco-friendly method has become a major challenge in the analytical chemistry field, a growing trend related to environmental awareness has emerged in recent years [5]. In this context, the dispersive liquid-liquid microextraction based on the solidification of a floating organic drop (DLLME-SFO) technique satisfies the general characteristics of green strategies.Nowadays, to establish an analytical methodology, not only the overall performance should be considered, but also the greenness assessment through a variety of metrics. Several green metrics can assess sustainability of analytical procedure, among them, the Analytical Eco-Scale, the Green certificate (GC), and the recently introduced Analytical GREEnness calculator (AGREE), are the most reported. In this work, the evaluation of the concentration levels of OTA in tea beverage samples developing extraction and preconcentration steps through the solidification of a floating organic drop combined with an additional octadecyl silane clean-up step is proposed. The obtained extract was analyzed by UHPLC-MS/MS. Interferences from the matrix were effectively reduced and, consequently, recovery increased from 43.18% ± 4.1% to 96.02% ± 2.54%. The validation assays were carried out by external and spiked samples calibration, with satisfactory recoveries. An adequate dynamic calibration range was obtained over a concentration interval between 0.5 and 70 μg mL-1 OTA. Capabilities of detection and quantification were 0.5 and 1.4 μg mL-1. Finally, the greenness assessment of the developed methodology was assessed by means of the green certificate, achieving the A performance [6].References1.Toman, J., et al., Transfer of ochratoxin A from raw black tea to tea infusions prepared according to the Turkish tradition. Journal of the science of food and agriculture, 2018. 98(1): p. 261-265.2.Sedova, I., M. Kiseleva, and V. Tutelyan, Mycotoxins in Tea: Occurrence, Methods of Determination and Risk Evaluation. Toxins, 2018. 10(11): p. 444.3.Commission, E., Commission Regulation (EC) No 1881/2006 of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs. Off J Eur Union, 2006. 364(365?324).4.Jia, W., et al., Multiplexing data independent untargeted workflows for mycotoxins screening on a quadrupole-Orbitrap high resolution mass spectrometry platform. Food chemistry, 2019. 278: p. 67-76.5.El-Deen, A.K. and K. Shimizu, Deep eutectic solvent as a novel disperser in dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFOD) for preconcentration of steroids in water samples: Assessment of the method deleterious impact on the environment using Analytical Eco-Scale and Green Analytical Procedure Index. Microchemical Journal, 2019. 149: p. 103988.6.Cina, M., et al., Development of a novel UHPLC-MS/MS method for the determination of ochratoxin A in tea. Heliyon, 2021. 7(4): p. e06663.