Not every compound responds to every ionization technique. Some compounds ionize only by electrospray ionization (ESI). Other compounds respond only to atmospheric pressure chemical ionization (APCI). When you analyze unknowns, you do not know ahead of time which mode to choose. Even when looking for target compounds, you need to know if an unexpected impurity is present. To be sure, you must exchange sources and reanalyze.
The Agilent multimode source is the only ion source capable of simultaneously acquiring ESI and APCI data—doubling throughput and making reanalysis a thing of the past. 
The Agilent multimode source can switch ion polarities on a scan-to-scan basis. With this rapid polarity switching, you can acquire positive and negative ESI and APCI data in a single run.  |