Analysis of human milk triacylglycerols by high-performance liquid chromatography with light-scattering detection

A high-performance liquid chromatography (HPLC) method for the separation of human milk triacylglycerols using a C18 Spherisorb ODS column and ternary gradient elution with dichloromethane, acetone and acetonitrile is described. The triacylglycerols are detected by light scattering. Several chromatographic conditions were assayed in order to optimize the method: sample solubility, mobile phase, column temperature and the mass detector oven temperature. The linearity, precision and relative response of the method were examined. A total of 34 peaks were separated and quantified based on the percentage peak area in the HPLC chromatogram. Mature human milk analyzed by this method contained six predominant triacylglyceride structures: POO, POL, LOO, POP, OOO and SOP, where P = palmitin, O = olein, L = linolein and S = stearin.