Lc msd trap vl

The extraction methods for anthocyanins, flavonols, and proanthocyanidins were referenced from Prior et al. (2001) (link); Lätti et al. (2010) (link), and Pertuzatti et al. (2016) (link), respectively. High performance liquid chromatography (HPLC) separation, identification and quantitation of anthocyanins, proanthocyanidins, and flavonols were performed on an Agilent 1100 Series system (Agilent, Germany), equipped with DAD (G1315B) and a LC/MSD Trap VL (G2445C VL) electrospray ionization mass spectrometry (ESIMSn) system that was coupled to an Agilent ChemStation (version B.01.03) data-processing station. The mass spectra data were processed with the Agilent LC/MS Trap software (Version 5.3).
ESI-MSn was used to identify the anthocyanins, proanthocyanidins, and flavonols profile and the following parameters were employed: positive ionization mode; dry gas, N2, 11 mL/min; drying temperature, 350°C; nebulizer, 65 psi; capillary, –2500 V; capillary exit offset, 70 V; skimmer1, 20 V; skimmer 2, 6 V; compound stability, 100%; scan range, 50–1,200 m/z. For the purposes of quantitation, For quantification, DAD chromatograms were extracted at 520 nm for anthocyanins, proanthocyanidins at 280 nm, and flavonols at 360 nm.

Individual phenolic compounds were measured using an HPLC-DADESI-MS/MS system as previously reported [3 (link)]. Briefly, the analysis was carried out on an Agilent 1100 series system (Agilent, Waldbronn, Germany) equipped with a photodiode array detector (DAD) and an LC/MSD Trap VL electrospray ionization mass spectrometry (ESI-MS/MS), both coupled with an Agilent ChemStation for data processing. Aliquots of phenolic extracts, obtained as described in Section 2.1, were evaporated in a rotary evaporator at 35 °C under vacuum and were eventually dissolved in 200 μL of methanol/water (20:80, v/v) by being sonicated (5 min) and vortexed (2 min) before injecting 20 μL in the system. Quantification of pistachio phenolics was performed using the DAD chromatograms recorded at 280 nm (flavanols, flavanones and phenolic acids), 360 nm (flavonols) and 520 nm (anthocyanins) using specific calibration curves [3 (link)].