Elemental mapping in plants using submilli-PIXE camera

We have developed an in-air PIXE analysis system which provides elemental distribution images in a region of 3x3 cm2 with a spatial resolution of ∼0.5 mm. We call this system an in-air submilli-PIXE camera. This system consists of a submilli-beam line, beam scanners and a data acquisition system for elemental mapping. We applied the in-air submilli-PIXE camera to phytoremediation research. Phytoremediation is a technology for cleaning metal-contaminated soils using plant physiology. Pteris vittata, which is known as a hyper-accumulator of As, was analyzed by the in-air submilli-PIXE camera. Elemental images of leaves were obtained in-vivo without sample preparation. Elemental map of the leaves showed that arsenic was accumulated in the edges of Pteris vittata leaves. From these findings, it is possible to reveal the distribution of heavy metals and their location in the plant using the submilli-PIXE camera. PIXE analysis is an effective tool for undertaking phytoremediation research. (author)