Fig. 7

Antibacterial effects of floating beads with/without tetracycline for different immersion periods. (a), (b) and (c) are core-shell beads (C/X=4/3) without tetracycline, and (d), (e) and (f) are core-shell beads (C/X=4/3) with tetracycline. (g) is non-core-shell alginate beads without tetracycline. The immersion time before antibacterial test is 0 hour for (a) (d), 2 hours for (b) (e), and 4 hours for (c) (f) and (g). The beads in (d), (e) and (f) encapsulate 69.9 μg tetracycline in total