Figure 2

Light microscopy of beads. Size and appearance of different size of blank beads (A–D) and bismuth-functionalized beads (7) (E–H) under light microscopy, (A, E) 100–160 μm, (B, F) 250–355 μm, (C, G) 355–425 μm and (D, H) 425–600 μm.