Figure 6.
Examples of enzyme-responsive drug release. (A) Mesoporous silica nanoparticles were surface-functionalized with choline-like chains via ester- or urea-based tethers and capped with sulfonatocalix[4]arene. Encapsulated cargo was released upon exposure to esterase or urease enzymes. Adapted with permission from reference 123. Copyright 2013 Royal Society of Chemistry. (B) A vesicle self-assembled from amphiphiles produced by the host-guest association of myristoylcholine and sulfonatocalix[4]arene. Encapsulated drugs were released upon exposure to butyrylcholinesterase, which degraded the myristoylcholine guest molecule and dissociated the amphiphilic complex. Adapted with permission from reference 124. Copyright 2012 American Chemical Society.