. Author manuscript; available in PMC: 2010 Nov 1.

Published in final edited form as: J Am Soc Mass Spectrom. 2009 Aug 12;20(11):1988–1996. doi: 10.1016/j.jasms.2009.07.021

Table 3. Figures of merit.

Ionization mode	Sensitivity	Selectivity	Applicability	Multimode use
ESI	fmol	n/a^a	peptides, proteins	yes^c
APCI	pmol	n/a^b	small molecules	yes^d
CD-ECI	zmol	yes	ferrocene labeled biomolecules, small molecules	yes^c

CD-ECI achieves selectivity according to the ionization potential of analytes vs. capillary material, ESI and APCI do not have this option

under standard HPLC-MS conditions; it should be noted though that APCI can be made selective by changing the nature of the ion-molecule chemistry

ESI and CD-ECI are interchangeable without hardware change

Hardware change (APCI probe) necessary