ONLINE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY COUPLED WITH HIGH-RESOLUTION GAS-CHROMATOGRAPHY AND MASS-SPECTROMETRY (HPLC-HRGC-MS) FOR THE ANALYSIS OF COMPLEX-MIXTURES CONTAINING HIGHLY VOLATILE COMPOUNDS

A comparision between high resolution gas chromatography coupled with mass spectrometry (GC-MS) and an ''on-line'' high performance liquid c hromatography, high resolution gas chromatography, mass spectrometry s ystem (HPLC-HRGC-MS) is described for the analysis of complex mixtures . The latter allowed mass spectra with a purity and fit indices higher than those obtained from the GC-MS analysis of the whole sample to be recorded. A quantitative comparision has been made using the two meth ods for neroli essential oil. The evaporation of the solvent is select ive in the ''on-line'' system, which prevents the loss, by co-evaporat ion, of even the most volatile components of the analyte.