Figure 8

Example of micro-PIXE analysis of a single BEAS-2B cell exposed to cobalt oxide particles (50 μg.mL⁻¹Co) for 72 h (IC25). Potassium distribution delineates the cell boundaries and the nucleus position (A). The highest fraction of cobalt is found within the cytoplasm in its particulate form. A small fraction of cobalt is solubilized as shown by the local PIXE spectrum inside (particulate fraction) and outside (solubilized fraction) cobalt oxide particles (B). In this example, approximately 0.1% cobalt was solubilized and diffused into the rest of the cytoplasm and the nucleus.