Radiation damage surface effects

In standard FAB, the surface of the matrix solution is depleted of analyte and suffers from radiational damage during elongated measurements. Refreshment of the surface proceeds by diffusion (limited by the viscosity of the matrix) or evaporation. Continuous-flow fast atom bombardment (CF-FAB) continuously refreshes the surface exposed to the atom beam. [107,108] The same effect is obtained in slightly different way by the frit-fast atom bombardment (frit-FAB) technique. [109,110] In addition, both CF-FAB and frit-FAB can be used for online-coupling of liquid chromatography (LC, Chap. 12) [111] or capillary electrophoresis (CE) to a FAB ion source. [112]... 

Single-component irradiations have provided useful information concerning certain projectile/surface interactions which contribute to plasma contaminant release and surface damage and erosion, but they cannot yield any information about interactive (synergistic) surface effects. These arise when two or more plasma radiation components interact simulaneously with surfaces, together producing plasma contaminant release and/or surface erosion either larger or smaller than that expected from a simple summation of the effects caused by the individual radiation components. Interactive effects can also occur after sequential irradiations. 

The situation regarding heterogeneous catalysis is rather confused. More fundamental research is needed to clarify the problem of whether certain elements, when implanted, cause specific chemical effects other than radiation damage. Moreover, it is an open question as to whether it is possible to vary the selectivity of a catalyst. Another difficulty is the standardization of the surfaces under study. Either one works under UHV conditions which have little relationship to practical applications, or under normal conditions which means that surface contaminations are unavoidable. 

Radiation damage may also occur from exposure to the skin. Medically, radioactive strontium probes have been used intentionally to destroy unwanted tissue on the surface of the eye or skin. The eye tissues sometimes become inflamed or abnormally thin after a long time. Thinning of the lower layer of the skin (dermis) has also been reported in animal studies as a delayed effect. In addition, skin and bone cancer were reported in animals that were irradiated on the skin by exposure to a radioactive strontium probe. 

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