Distribution of Cell Wall Components by TOF-SIMS

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) is an analytical method that has developed just within the last few decades. It is a kind of imaging mass spectrometry and supplies mass information with a submicron lateral resolution. In this chapter, the availability of TOF-SIMS measurements in the research field of woody plants is introduced. The main polymer components of the plant cell wall, cellulose, hemicellulose, and lignin are detected as fragment ions. The comprehension of the fragmentation behavior is essential to interpret the complicated mass spectra of biological samples, and the case of lignin is specifically described. Inorganics and low-molecular-weight extractives are detectable as they are. The latest topics of cryo-TOF-SIMS dealing with frozen-hydrated samples are also presented. Heterogeneous distribution of many chemical components in plants at dried or frozen-hydrated conditions might be useful information to improve our discussion another notch.