The supernatant (500 lL) was transferred to a 2 mL tube containing 150 mg of magnesium sulfate, 50 mg of Florisil and 50 mg of PSA for clean-up, and submitted to vortex and centrifugation as already described. Finally, an aliquot of supernatant was transferred to a vial followed by injection at the UHPLC–MS/MS system. The choice of the amount of honey sample and water for dilution as well as the type of extraction solvent and clean-up salts was based on data from recovery and sample cleaning.