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[EN] Herein, a novel drug photorelease system based on gold nanostars (AuNSts), coated with a mesoporous silica shell and capped with paraffin as thermosensitive molecular gate, is reported. Direct measurements of the surface temperature of a single gold nanostar irradiated using a tightly focused laser beam are performed via a heat sensitive biological matrix. The surface temperature of a AuNSt increases by hundreds of degrees (degrees C) even at low laser powers. AuNSts coated with a mesoporous silica shell using a surfactant-templated synthesis are used as chemotherapeutic nanocarriers. Synthetic parameters are optimized to d avoid AuNSt reshaping, and thus to obtain nanoparticles with suitable and stable plasmonic properties for near-infrared (NIR) laser-triggered cargo delivery. The mesoporous silica-coated nanostars are loaded with doxorubicin (Dox) and coated with octadecyltrimethoxysilane and the paraffin heneicosane. The paraffin molecules formed a hydrophobic layer that blocks the pores, impeding the release of the cargo. This hybrid nanosystem exhibits a well-defined photodelivery profile using NIR radiation, even at low power density, whereas the nonirradiated sample shows a negligible payload release. Dox-loaded nanoparticles displayed no cytotoxicity toward HeLa cells, until they are irradiated with 808 nm laser, provoking paraffin melting and drug release. Hence, these novel, functional, and biocompatible nanoparticles display adequate plasmonic properties for NIR-triggered drug photorelease applications., The authors gratefully acknowledge financial support from the Spanish Government (Projects AGL2015-70235-C2-2-R and MAT2015-64139-C4-1-R), the Generalitat Valenciana (Project PROMETEOII/2014/047), and European Union (Programme European Union Action 2 Erasmus Mundus Partnerships, Grant-2014-0870/001-001). A. Samadi and L. B. Oddershede acknowledge financial support from the Novo Nordisk Foundation (NNF14OC0011361) and from the Danish National Research Foundation (DNRF116). A. H. Montoto thanks Erasmus Mundus Programme for his PhD scholarship at EurolnkaNet project. The authors thank UPV electron microscopy and CIPF confocal and electron microscopy services for technical support.

[EN] Gold nanostars coated with a mesoporous silica shell and functionalized with poly(ethylene glycol) containing photolabile 2-nitrobenzyl moieties are able to release doxorubicin after NIR light irradiation at low power irradiance via a multiphoton absorption photo-dissociation process., The authors gratefully acknowledge financial support from the Spanish Government (projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/AEI/FEDER,UE)), the Generalitat Valenciana (Project PROMETEO2018/024) and the European Union (Programme European Union Action 2-Erasmus Mundus Partnerships, Grant Agreement Number-2014-0870/001-001). A.H.-M. thanks the Erasmus Mundus Programme for his PhD scholarship for the EuroInkaNet project.

[EN] Janus gold nanostar-mesoporous silica nanoparticle (AuNSt-MSNP) nanodevices able to release an entrapped payload upon irradiation with near infrared (NIR) light were prepared and characterized. The AuNSt surface was functionalized with a thiolated photolabile molecule (5), whereas the mesoporous silica face was loaded with a model drug (doxorubicin) and capped with proton-responsive benzimidazole-beta-cyclodextrin supramolecular gatekeepers (N 1). Upon irradiation with NIR-light, the photolabile compound 5 photodissociated, resulting in the formation of succinic acid, which induced the opening of the gatekeeper and cargo delivery. In the overall mechanism, the gold surface acts as a photochemical transducer capable of transforming the NIR-light input into a chemical messenger (succinic acid) that opens the supramolecular nanovalve. The prepared hybrid nanoparticles were non-cytotoxic to HeLa cells, until they were irradiated with a NIR laser, which led to intracellular doxorubicin release and hyperthermia. This induced a remarkable reduction in HeLa cells viability., The authors gratefully acknowledge financial support from the Spanish Government [Projects MAT2015-64139-C4-1-R, AGL2015-70235-C2-2-R and SAF2017-84689-R (MINECO/AEI/FEDER, UE)], the Generalitat Valenciana (Project PROMETEO2018/024) and European Union (Erasmus Mundus Programme, Action 2, grant agreement number 2014-0870/001001). A.H. thanks the Erasmus Mundus Programme for his PhD scholarship through the EuroInkaNet project. A.L.-L. thanks "La Caixa" Banking Foundation for his PhD scholarship.