Determination of phospholipids by HPLC
Methanolic extracts of oils were evaporated and the residue
was dissolved in hexane/2-propanol (3:2). This solution was analyzed
by HPLC in a Waters 2695 Module (Milford, MA) equipped
with an evaporative light scattering detector (Waters 2420 ELSD).
Polar and neutral lipids were separated at 30 C using a Lichrospher
100 Diol 254-4 (5 lm) column (Merck, Darmstadt, Germany)
or a normal phase Lichrocart 250-4 (5 lm) column (Merck). In all
cases the flow rate was 1 mL min1, and samples were dissolved
in the same solvent as that used to equilibrate the column at the
time of injection. Data were processed using Empower software,
and the ELSD was regularly calibrated using commercial high-purity
standards for each lipid (Salas, Martínez-Force, & Garcés, 2006).