The establishment of EVISA is funded by the EU through
the Fifth Framework Programme (G7RT- CT- 2002- 05112).
Supporters of EVISA includes:
reconstructed ion chromatogram
A normal mass spectrometric data set consists of full mass spectra recorded sequentially in time as sample is admitted to the ion source, either from a direct-insertion probe or from a chromatograph (for example, GC/MS). The total ion current trace is the sum of ion abundances in each mass spectrum plotted versus time. Clearly each mass spectrum will also contain a pattern of molecular and fragment ions. Ions of these particular masses can be specified, and the data system can plot the scan-by-scan abundances of these specific ions versus time, which is known as a reconstructed ion chromatogram. The reconstructed ion chromatogram can be used to identify all ions that belong together in a single mass spectrum by virtue of their coincident peaks in time (and discriminate against background ions), and can also be used to screen a GC/MS run for related classes of compounds by reconstruction of ion chromatograms for common structurally specific ions.