APPLICATIONS OF PIXE IN THE LIFE SCIENCES

During the last decade, particle-induced X-ray emission spectrometry ( PIXE) has been accepted by the analytical chemistry community as a sta ndard method. Instead of routine bulk analysis of biomedical samples w here several competing analytical techniques are available, the full s trength of PIXE could be exploited in special applications where also location of the detected ions is desirable. In this article, two diffe rent approaches for this purpose are discussed and illustrated: (1) nu clear microscopy, where micro-PIXE utilizing a proton beam spot of app rox 1 mu m(2) or less promises unique perspectives to obtain elemental maps at the cellular level, and (2) in situ PIXE analysis of the minu te metalloprotein volumes concentrated in thin-layer electrophoretogra ms.