In our work, chromatographic analysis was performed on an
Agilent 1200 system (Palo Alto, CA, USA) consisting of a quaternary
pump, vacuum degasser, autosampler and a diode array detector
(DAD). A Phenomenex Kinetex-C18 (Torrance, CA, USA) column
(100 4.60 mm internal diameter, 2.6 lm particle size) was used
for chromatographic separation. The column temperature was held
at 30 C. The mobile phase was water (0.1% trifluoroacetic acid) at a
flow rate of 0.6 mL/min. The detection wavelength was set at
245 nm.