. Author manuscript; available in PMC: 2014 Dec 1.

Published in final edited form as: Bioanalysis. 2014 Feb;6(4):525–540. doi: 10.4155/bio.13.341

Table 1.

Comparison of MS imaging approaches detailing ionization methods, mass analyzers, optimal analytes, mass range and spatial resolution.

Type of MSI	Ionization source	Common mass analyzer	Optimal analytes	Mass range (Da)	Spatial resolution (μm)
MALDI	UV/IR laser Soft ionization	TOF	Lipids, peptides, proteins, small molecules	0–50,000	30–50
SIMS	Ion gun Hard ionization	TOF Magnetic sector Orbitrap	Lipids, small peptides, small molecules	0–2000	0.5–1
DESI	Solvent spray Soft ionization	Orbitrap	Lipids, peptides, small molecules	0–2000	100

MSI: MS imaging; SIMS: Secondary ion MS.