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Photo-redox activated drug delivery systems operating under two photon excitation in the near-IR.

ABSTRACT: We report the design and synthesis of a nano-container consisting of mesoporous silica nanoparticles with the pore openings covered by "snap-top" caps that are opened by near-IR light. A photo transducer molecule that is a reducing agent in an excited electronic state is covalently attached to the system. Near IR two-photon excitation causes inter-molecular electron transfer that reduces a disulfide bond holding the cap in place, thus allowing the cargo molecules to escape. We describe the operation of the "snap-top" release mechanism by both one- and two-photon activation. This system presents a proof of concept of a near-IR photoredox-induced nanoparticle delivery system that may lead to a new type of photodynamic drug release therapy.

SUBMITTER: Guardado-Alvarez TM

PROVIDER: S-EPMC4305343 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Photo-redox activated drug delivery systems operating under two photon excitation in the near-IR.

Guardado-Alvarez Tania M TM Devi Lekshmi Sudha LS Vabre Jean-Marie JM Pecorelli Travis A TA Schwartz Benjamin J BJ Durand Jean-Olivier JO Mongin Olivier O Blanchard-Desce Mireille M Zink Jeffrey I JI

Nanoscale 20140501 9

We report the design and synthesis of a nano-container consisting of mesoporous silica nanoparticles with the pore openings covered by "snap-top" caps that are opened by near-IR light. A photo transducer molecule that is a reducing agent in an excited electronic state is covalently attached to the system. Near IR two-photon excitation causes inter-molecular electron transfer that reduces a disulfide bond holding the cap in place, thus allowing the cargo molecules to escape. We describe the opera ...[more]

PMID: 24647752

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