Lc 10atvp binary pump

The LC-10A HPLC (Shimadzu, Kyoto, Japan) was equipped with LC-10ATvp binary pump (Shimadzu, Kyoto, Japan), SIL-10A autosampler (Shimadzu, Kyoto, Japan), and SPD-M10Avp detector (Shimadzu, Kyoto, Japan). The instrument was controlled by a computer and the Lab Solutions (Shimadzu, Kyoto, Japan) chromatography workstation was used to analyze the data. To obtain better chromatographic peaks of zeaxanthin and lutein, various mobile phase systems were optimized, and the optimal chromatographic separation conditions were determined. The Shimadzu^® C18 column (4.6 mm × 250 mm, 5 μm; Kyoto, Japan) was used for the analysis of the zeaxanthin and lutein contents. The optimum chromatographic conditions for the flow rate, detection wavelength, column temperature, and the injection volume were selected as 1.0 mL/min, 450 nm, 25 °C, and 20 μL, respectively. The mobile phase consisted of acetonitrile/dichloromethane (95:5, v/v).

A DGU-20A 5R series UHPLC system equipped with a LC-10ATvp binary pump (SHIMADZU, Japan) was used for UHPLC–MS/MS analysis. A 5500 triple quad tandem mass spectrometer equipped with electrospray ionization source (AB Sciex, Concord, OH, Canada) was used for mass spectrometry. The mobile phase was composed of a mixture of 0.1% formic acid aqueous solution (A) and acetonitrile (B) with a gradient elution program (0–0.1 min, 40% B; 0.1–2.5 min, 40–95% B; 2.5–3.5 min, 95% B; 3.5–4.5 min, 95–40% B; 4.5–5.0 min, 40% B). The flow rate was set at 0.3 mL/min and the injection volume was 5 µL. The ESI source was operated in positive ionization mode. The mass spectrometer was operated in multiple reactions monitoring (MRM) mode and the selected monitor ions were m/z 649.4/151.1 for yuanhuacine and m/z 748.5/590.4 for IS. The optimized parameters were as follows: ion source temperature (TEM), 550 °C; curtain gas (CUR), 35 psi; ion source gas 1 (GAS1), 55 psi; ion source gas 2 (GAS2), 55 psi; ion spray voltage (IS), 5500 V.