A new method based on ultra performance convergence chromatography (UPC2)
was developed for analysis of free amino acids in fruit wine. They were separated on an Acquity UPC2Torus Diol (3.0 ×100mm, 1.7 μm) with a mobile phase consisted of
supercritical CO2and
methanol: acetonitrile (1: 1 v/v, with 2.5
mmol/L ammonium acetate as mobile phase modifier), the flow rate is 2.0 mL/min
and DAD detection was set at 280 nm with a compensation range of 330-430 nm,
back pressure is 1800 psi. The results showed good linearity (R2=
0.9990-0.9998)
and high resolution higher than 1.22. The limits of detection (LOD) and
quantification (LOQ) ranged from 23-57 ng/L and 70-178 ng/L, respectively. The
linear range was between 20 and 400 μg/mL.
The spiked recoveries were ranged from 85.6% to 101.12%. It was applied for the free amino acids analysis
of selected pitaya wine, which could also provide a new method for the analysis
of free amino acid distribution in other food matrix from different sources.