Uv spd m20a diode array detector

HPLC analyses were performed with an HPLC Shimadzu LC-10AD VP instrument (Tokyo, Japan) equipped with a binary pump LC-10AD VP, a UV SPD-M20A Diode Array detector, a 20 µL injector and a computer integrating apparatus (EZ Start 7.4 software, Shimadzu Scientific Instruments, Inc., Columbia, MD, USA). Chromatographic separation was achieved on a reversed-phase column ACE^® EXCEL 5 C18-AMIDE (5 µm, 4.6 mm × 125 mm), a mobile phase consisted of methanol (A) acetate buffer 5 mM pH 6.5 (B). For separation the gradient method was developed as follows: A: B (0.5:99.5→0.01–3.00 min, 80:20→3.00–7.00 min; 80:20→7.00–22.00 min; 0.5:99.5→22–26 min). The flow rate was set at 1 mL/min, the UV wavelength range 200–700 nm and set 428, 310 and 250 nm to identification of MTR, CUR and GA, respectively. In these conditions the retention time of MTR, CUR and GA were 1.95, 12.42 and 15.68 min, respectively.
For CUR quantification, the calibration curve was performed in the concentration range of 0.0075–0.01 mg/mL. HPLC reports were highly reproducible and linearly related to concentration (R = 0.999).

HPLC analyses were performed with a HPLC Shimadzu LC-10AD VP instrument (Tokyo, Japan) equipped with a binary pump LC-10AD VP, a UV SPD-M20A Diode Array detector, a 20 μL injector and a computer integrating apparatus (EZ Start 7.4 software, Shimadzu Scientific Instruments, Inc., Columbia, MD, USA). Chromatographic separation was achieved on a reversed-phase column SeQuant^® Zic^®-Hilic, (5 μm, 200 Å, 150 × 2.1 mm, Merck, Germany), a mobile phase consisted of acetate buffer 5 mM pH 6.5 (A) and Acetonitrile (B). For separation of AFA components the gradient method was developed as follows: A:B (0.5:99.5→0.01–5.00 min, 40:60→5.00–11.00 min; 40:60→11.00–30.00 min). The flow rate was set at 0.3 mL/min, the UV wavelength range 200–700 nm and set at 260, 334, 407, 665 nm to identification.

The system used was a Shimadzu^® Prominence (Shimadzu Corporation, Kyoto, Japan) consisting of a LC-20AT pump, a SPD-M20A UV diode array detector, CTO-20 AC column oven, and a LabSolutions software (Version 5.51, Shimadzu Corporation, Kyoto, Japan). A MultoHigh 100 RP 18, 5 μ column (250 × 4.6 mm) (CS—Chromatographie Service GmbH, Langerwehe, Germany) was used. The temperature was set at 30 °C. The HPLC analyses were performed using a linear gradient solvent system consisting of methanol:acetonitrile 50:50 (A) and 0.1% formic acid in water (B) with a flow rate of 0.4 mL/min as follows: initial conditions were 8% A and 92% B; 0–10 min: 92% to 85% B; 10–25 min: 85% to 70% B; 25–35 min: 70% to 65% B; 35–45 min: 65% to 55% B; 45–55 min: 55% to 50% B; 55 to 75 min: 50% to 45% B; 75 to 95 min: 45% to 35% B; 95 to 100 min: 35% to 25% B; 100 to 105 min: 25% B; 105 to 110 min: 25% to 40% B; 110 to 120 min: 40% to 60% B; 120 to 130 min: 60% to 75% B; 130 to 135 min: 75% to 92% B; 135 to 145 min: back to 92% B (initial condition). The volume injected was 20 μL. The compounds were monitored at 254, 280, and 330 nm. UV spectra of the compounds detected were recorded from 200 to 500 nm for peak characterization.