Figure 3

The X-ray peaks for each element obtained by in-air micro-PIXE analysis of alveolar macrophages from the surfactant-rich area in PAP and control lung. The microbeam was focused on a 54 μm × 61 μm area of the PAP lung tissue. Peaks display the characteristic X-ray signatures for each element, as shown by the counts (a). High peaks of S, Ca, and Fe were detected. The peak for Fe Kβ is near the peak of cobalt. The microbeam was focused on a 54 μm × 61 μm area of the control lung tissue (b). Peaks of S and Fe were lower than PAP lung tissue.