Abstract
Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) can be used for mass spectrometry and imaging of inorganic and organic components on surfaces. Full spectral information for each pixel down to sub-micron resolution provides a means to study protein interactions with interfaces in highly heterogeneous structures, assemblies and mixtures; patterned arrays; or simultaneous correlation with other chemical features (gradients, spatial arrangements etc). With careful spectral analysis and interpretation, indications of protein orientation, bonds and structural changes can be investigated. ToF-SIMS, with highly sensitive mass fragmentation patterns and high spatial resolution provides complementary information in systems with structurally complex arrangements, chemical heterogeneity and multicomponent mixtures. ToF-SIMS analysis of proteins at interfaces offers unique complementary information which is described here in the context of understanding protein interactions at interfaces with examples of nano- and micro-scale structures. The use for complementary characterization of surface chemical properties which relate to protein interactions is also emphasized. © 2012 American Chemical Society.