DEVELOPMENT OF AN HPLC DIODE-ARRAY DETECTOR METHOD FOR SIMULTANEOUS DETERMINATION OF 7 HYDROXYCINNAMIC ACIDS IN GREEN COFFEE/

A simple, rapid, sensitive, reproducible, and accurate reverse phase H PLC procedure is proposed for the determination of seven phenolic acid s in green coffee samples. The sample preparation was simple, involvin g extraction, alkaline hydrolysis, and liquid/liquid extraction. The c hromatographic separation was achieved using a reverse phase column Sp herisorb ODS2 (5 mu m; 25.0 x 0.46 cm). Gradient elution was carried o ut using water-formic acid (19:1) (A) and methanol (B). The effluent w as monitored by a diode-array detector and chromatograms were recorded at 320 nm. The detection limit value of the method was 0.09 mu g/mL a nd the method was precise (CV% = 0.5%; n = 10). Recovery values of caf feic acid from spiked green coffee samples were between 88.3 and 93.2% .