Matrix solid-phase dispersion for the liquid chromatographic determination of phenolic acids in Melissa officinalis.

Matrix solid-phase dispersion (MSPD) was used for sample preparation of plant material (Melissa officinalis, Lemon Balm) prior to liquid chromatography of rosmarinic, caffeic and protocatechuic acids, phenolic compounds present in this herb. Different MSPD sorbents and various elution agents were tested and the optimal extraction conditions determined with the aim to obtain extraction recoveries greater than 90% for all analytes.