Polyphenol Profiling by HPLC-QTOF-MS

Profiling of polyphenols from samples was achieved by an already published method [20 (link)] by using HPLC system (Agilent 1200 series) coupled to Agilent 6520 Accurate-Mass Q-TOF LC/MS (Agilent Technologies, Santa Clara, CA, USA) with an electrospray ionisation source (ESI). Separation of compounds was performed with RP-80A Column (250 mm × 4.6 nm, 4 µm). Mobile phases (A) and (B) were composed of water/acetic acid solution (98:2 v/v) and water/acetonitrile/acetic acid (50:49.5:0.5, v/v/v) respectively and elution program was set as: 0–20 min linear gradient from 90% to 75% eluent A; 20–30 min linear gradient from 75% to 65% eluent A; 30–40 min linear gradient from 65% to 60% eluent A; 40–70 min linear gradient from 60% to 45% eluent A; 70–75 min linear gradient from 45% to 20% eluent A; 75–77 min linear gradient from 20% to 0% eluent A; 77–79 min linear gradient from 0% eluent A; 82–85 min linear gradient from 0% to 90% eluent A. The flow rate was maintained at 0.8 mL/min. Sample injection volume was 6 µL. Peaks were identified in negative and positive ionisation modes. Mass spectra were obtained in the m/z range of 50–1300. Data were analyzed on an Agilent LC/MS/QTOF Mass Hunter Data Acquisition Software (Version B.03.01).