Ultra-high-performance liquid chromatography (UHPLC) was
made on a Waters Acquity UPLC system from Waters (Milford,
MA, USA), equipped with a binary solvent delivery system, an
autosampler, and a BEH C18 (2.1 × 50 mm, 1.7 m) column. MS–MS
acquisitions were performed in a Waters Acquity triple quadrupole
MS detector, equipped with a Z-spray electrospray ionization
source.