Search

Abstract: Periodic mesoporous organosilica nanoparticles emerge as promising vectors for nanomedicine applications. Their properties are very different from those of well‐known mesoporous silica nanoparticles as there is no silica source for their synthesis. So far, they have only been synthesized from small bis‐silylated organic precursors. However, no studies employing large stimuli‐responsive precursors have been reported on such hybrid systems yet. Here, the synthesis of porphyrin‐based organosilica nanoparticles from a large octasilylated metalated porphyrin precursor is described for applications in near‐infrared two‐photon‐triggered spatiotemporal theranostics. The nanoparticles display unique interconnected large cavities of 10–80 nm. The framework of the nanoparticles is constituted with J‐aggregates of porphyrins, which endows them with two‐photon sensitivity. The nanoparticle efficiency for intracellular tracking is first demonstrated by the in vitro near‐infrared imaging of breast cancer cells. After functionalization of the nanoparticles with aminopropyltriethoxysilane, two‐photon‐excited photodynamic therapy in zebrafish is successfully achieved. Two‐photon photochemical internalization in cancer cells of the nanoparticles loaded with siRNA is also performed for the first time. Furthermore, siRNA targeting green fluorescent protein complexed with the nanoparticles is delivered in vivo in zebrafish embryos, which demonstrates the versatility of the nanovectors for biomedical applications. [ABSTRACT FROM AUTHOR]

Gemcitabine hydrochloride is an FDA-approved chemotherapeutic drug used in the treatment of various cancers. Several drawbacks of gemcitabine, including its short in vivo half-life of 8-17 min associated with a rapid excretion by the kidneys and its poor membrane permeability, have inspired research on a nanodelivery approach. In this study, we report ethylene-based periodic mesoporous organosilica nanoparticles (PMOs) for photodynamic therapy and the autonomous delivery of gemcitabine in cancer cells. Porphyrins were used as photosensitizers and were localized in the walls of the PMOs while a high loading capacity of gemcitabine was observed in the porous structure. Depending on the nature of the photosensitizer, and its aggregation state, we were able to perform one or two-photon photodynamic therapy. Two-photon excited photodynamic therapy combined with gemcitabine delivery led to a synergy and a very efficient cancer cell killing. [ABSTRACT FROM AUTHOR]