Fig. 4.

Silicon Beads. 1000 and 50 nm beads aliquoted from commercial stock (A). The beads can be difficult to resuspend, and the smaller they are the harder it will be. (B) shows 1000 nm beads immediately after re-addition of water, and the increased opacity can clearly be seen; the inset shows how they appear in suspension. (C) shows the same for 50 nm beads, and it is clear that the beads remain largely in the pellet, and that the pellet is more difficult to see.