To confirm that both alginate and fibril clusters constitute the capsules, we conducted a dissolution test by separately degrading calcium alginate and fibril clusters in the capsules (Fig. ). The hybrid capsules can be fully destroyed after soaking in 150mM sodium citrate solution (Fig. ), or cell culture medium supplemented with 0.25% trypsin-EDTA (Fig. ). With the rupture of capsules, macromolecules can rapidly release into the surrounding aqueous environment, as shown by releasing FITCdextran (Mw: 2 million) from these capsules. When the hybrid capsules are immersed in a diluted 0.125wt% trypsin-EDTA solution, the lifetime of capsule is extended by a few hours (Fig. ). These observations suggest that the lifetime of capsules can be controlled by varying the enzyme activity in the surrounding aqueous environment.