Biological tissue imaging with time-of-flight secondary ion mass spectrometry and cluster ion sources.
Time-of-flight secondary ion mass spectrometry (TOF-SIMS) using liquid metal ion guns (LMIGs) is now sensitive enough to produce molecular-ion images directly from biological tissue samples. Primary cluster ions strike a spot on the sample to produce a mass spectrum. An image of this sample is achieved by rastering the irradiated point over the sample surface. The use of secondary ion mass spectrometry for mapping biological tissue surfaces provides unique analytical capabilities; in particular, it enables in a single acquisition a large variety of biological compounds to be localised on a micrometer scale and scrutinised for colocalisations. Without any treatment of the sample, this method is fully compatible with subsequent and complementary analyses like fluorescence microscopy, histochemical staining, or even matrix-assisted laser desorption/ionisation imaging. Basic physical concepts, required instrumentation (ion source and mass analyzer), sample preparation methods, image acquisition, image processing, and emerging biological applications will be described and discussed.
Brunelle
Alain
A
Laboratoire de Spectrométrie de Masse, Institut de Chimie des Substances Naturelles, CNRS, UPR 2301, Av. de la Terrasse, F91198, Gif- sur- Yvette Cedex, France. Alain.Brunelle@icsn.cnrs-gif.fr
Touboul
David
D
Laprévote
Olivier
O
D000818:Animals; D001923:Brain Chemistry; D016000:Cluster Analysis; D007091:Image Processing, Computer-Assisted; D051381:Rats; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*