As3500 autosampler

Starting from the analytical conditions reported in literature,^{19 (link)} the column length was decreased from 250 mm to 150 mm (Hypersil BDS C18, 5 μm, 150×4.6 mm, Thermo Scientific, MA, USA) in order to improve tailing factors of the two active ingredients. A Thermo Fisher HPLC system equipped with a P4000 pump and an AS3500 autosampler were employed (Thermo Fisher Scientific Inc., Waltham, MA, USA). A Thermo Scientific UV6000 PDA was set at 250 nm for SX and 238 nm for FP, while the retention time was 3.0 and 6.7 min for SX and FP, respectively. LOQ was about 0.043 μg/mL for salmeterol and 0.035 μg/mL for fluticasone propionate. The linearity of response of salmeterol and fluticasone propionate was evaluated on standard solutions in the concentration range 0.04–13 μg/mL and 0.04–90 μg/mL, respectively, with a correlation coefficient R²: ≥0.99 in both of the cases.

Cranberry A6 was dissolved in deionized water to create a final concentration of 20 mg/mL. This solution was syringe-filtered (0.45 µm) into autosampler vials and injections were made on a 21.2 × 250 mm Rezex RSO-Oligosaccharide Ag+ 4% preparative column (Phenomenex, Torrance, CA, USA) with a particle size of 12 um and a Rezex Ag+ 15 × 21.2 mm ID guard cartridge (Phenomenex). The HPLC system also included an AS3500 Autosampler (Thermo Scientific,), a Model 303 gradient pump (Gilson, Inc., Middleton, WI, USA), an RID-10A refractive index detector (Shimadzu, Inc., Columbia, MD, USA), and an UltiMate 3000 fraction collector (Dionex, Sunnyvale, CA, USA). Deionized water was used as the mobile phase, with a constant flow rate of 1.0 mL/min. The column was heated to 80 °C. Injections of 200 µL were made onto the column every 75 min. Three fractions were collected based on the positions of the three most prominent peaks. Like fractions were combined, frozen, and lyophilized.