A high-performance liquid chromatography method using an alternative pentafluorophenyl (PFP) core-shell stationary phase has been developed and used for rapid separation of 23 anthocyanins in a highbush blueberry Bluehaven cultivar. A high efficiency of separation of anthocyanins was achieved in the core-shell column Kinetex PFP, 150x4.6 mm (particle size 2.6 mu m) with a 5x4.6 mm precolumn, using a simple linear gradient elution with a mobile phase of acetonitrile and a water solution of 2% formic acid at a flow rate of 1.0 ml/min and at a temperature of 50 degrees C.
The detection wavelength was set at 520 nm for detection of all anthocyanins. The homogenized blueberry sample (Bluehaven cultivar) was extracted using pure methanol with 1.3% formic acid using an ultrasound bath for 20 min and then filtrated.
A 5 mu L sample volume was directly injected into the HPLC system. The developed method showed an efficient separation of 23 anthocyanins in a total runtime of 21 min.
The potential of the pentafluorophenyl phase for efficient separation was demonstrated on a wide range of anthocyanins varying in glycosylation and acylation patterns found in highbush blueberries. The fluorinated stationary phase showed an alternative and complementary separation approach providing unique aromatic and polar selectivity in comparison with common C-18 phases.