A Multidimensional UHPLC-DAD-QTOF-IMS Gradient Approach for Qualitative and Quantitative Investigation of Citrus and Malus Fruit Phenolic Extracts and Edibles

A simple, rapid, and reproducible method for detecting 16 phenolics including marker flavonoids, polymethoxyflavones (PMFs), dihydroxychalcones, and phenolic acids was developed using ultrahigh-performance liquid chromatography-diode array detector-quadrupole time-of-flight-ion mobility mass spectrometry (UHPLC-DAD-QTOF-IMS). The effectiveness of the method was assessed through limit of detection (0.0009–0.16 μg/mL), limit of quantification (0.0027–0.45 μg/mL), and standard calibrations to validate at an optimized flow rate of 0.2 mL/min. Hesperidin as a major flavonoid and tangeretin as a PMF were quantified in Citrus extracts, whereas phloridzin, a major dihydroxychalcone, was quantified in Malus fruit. Freeze-dried and market edibles were also analyzed, compared, and quantified. The two-dimensional IMS mode confirmed the presence of naringin, hesperidin, nobiletin, and tangeretin in Citrus at frame numbers 666, 706, 1260, and 1301, respectively, in the positive mode. Similarly, Malus samples showed phloretin and phloridzin confirmed at 890 and 1198 frames, respectively, in the negative mode. The present analytical approach aids the higher applicability in quality assurance and development of food and phenolic extracts derived from Citrus and Malus fruits in a single shot.