Fig. 9.

SEM images of immobilized G. oxydans 621H cells. The cells were immobilized in alginate gel beads or alginate gel beads with Fe₃O₄ nanoparticles. After 3 days of sulfide oxidation and incubation (Fig. 7 legend), the beads were analzyed by SEM. The G. oxydans 621H cells were embedded in the gel beads. a Inside of the gel beads; b inside of the gel beads with Fe₃O₄ nanoparticles; c surface of the gel beads; d surface of the gel beads with Fe₃O₄ nanoparticle