Study of amino acids by means of liquid chromatography mass spectrometry: optimization of the particle–beam interface Original Research Article

Eleven amino acids have been analyzed by liquid chromatography-mass spectrometry with a particle beam (PB) interface and their library searchable electron impact spectra have been obtained. Particular attention was paid to the optimization of the PB interface. Toward this aim an experimental design approach was also used. Various variables influencing the analyte delivery to the mass spectrometer were considered and their respective effect on sensitivity was studied. The results obtained suggest that parameters usually neglected during the optimization step, as the chromatographic flow, are very important for the best performance of the PB interface and, since they show complex interactions, a multivariate approach is very useful to find the optimal values.