3.4.2. Chromatographic Conditions

An isocratic mobile phase consisting of a phosphate-buffered solution (pH 6.4) and acetonitrile (60:40, *v*/*v*) was vacuum filtered through a 0.45 µm membrane (Millipore®, Germany) and degassed by ultrasonication for 15 min. The flow rate of the mobile phase was 1.0 mL/min. Before sample injections, the system was cleaned with purified water for 60 min and was left to equilibrate with the mobile phase for 60 min. The oven was set at 25 ± 3 ◦C and UV detection was performed at 237 nm. For each analysis, sample volumes of 20 µL were injected in triplicate (*n* = 3).
