Signal‐Induced Release of Guests from a Photolatent Metal–Phenolic Supramolecular Cage and Its Hybrid Assemblies

The coordination chemistry of plant polyphenols and metal ions can be used for coating various substrates and for creating modular superstructures. We herein explored this chemistry for the controlled release of guests from mesoporous silica nanoparticles (MSNs). The selective adsorption of tannic acids (TAs) on MSN silica walls opens the MSN mesoporous channels without disturbing mass transport. The channel may be closed by the coordination of TA with Cu^II ions. Upon exposure to light, photolysis of Trojan horse guests (photoacid generators, PAGs) leads to acid generation, which enables the release of payloads by decomposing the outer coordination shell consisting of TA and Cu^II. We also fabricated a modular assembly of MSNs on glass substrates. The photoresponsive release characteristics of the resulting film are similar to those of the individual MSNs. This method is a fast and facile strategy for producing photoresponsive nanocontainers by non‐covalent engineering of MSN surfaces that should be suitable for various applications in materials science.     

Inside Cover: Cognitive‐Performance Recovery of Alzheimer's Disease Model Mice by Modulation of Early Soluble Amyloidal Assemblies (Angew. Chem. Int. Ed. 11/2009)

The accumulation of amyloid‐β (Aβ) as amyloid fibril deposits may play a central role in the pathogenesis of Alzheimer's disease, which is among the most common diseases of the 21st century. E. Gazit and co‐workers describe in their Communication on page 1981 ff. a novel Aβ fibrilization inhibitor, whose mechanism of action is based on targeting aromatic recognition modules together with a unique C^α‐methylation β‐breakage strategy. We thank Tal Mazor for the graphical assistance with the cover.