Application of Integrated Techniques for Micro- and Nano-imaging Towards the Study of Metallomics and Metalloproteomics in Biological Systems

Abstract

Nuclear imaging techniques can provide visible information on distribution patterns of metals or metalloids in various biological tissues, cell and subcellular fractions, and even at molecular level. Since the changes of not only its concentration but also spatial distribution for a specific element may cause some physiological problems even death, it is crucial to know the exact distribution in various organisms. In this chapter we introduce some imaging techniques (here mainly refers to the two-dimensional (2D) elemental distributions in samples) that are developing or have been used for metallomics and metalloproteomics. These techniques include not only modern nuclear analytical imaging techniques such as X-ray Fluorescence (XRF) in Section 1 and Particle Induced X-ray Emission (PIXE) in Section 2, but also non-nuclear analytical techniques such as Mass spectrometry imaging (MSI) technique in Section 3. We demonstrate their applications on the elemental imaging in animal tissues, plant leaves, nematodes, mammalian cells and so on. In addition to 2D imaging techniques, in Section 4, we also briefly introduce tomography, a three-dimensional imaging technique which can be done in vivo. All these techniques have successful applications in multidisciplinary study. Finally, in Section 5 we summarize the important characteristics of these techniques. Actually, each elemental imaging technique has its own characteristics. But for those researchers who engage in metallomics and metalloproteomics, the most important thing is to make a better understanding and use of these techniques. We hope that this chapter will be helpful.