Phosphorescent Oxygen Sensor with Dendritic Protection and Two-Photon Absorbing Antenna
- 28 July 2005
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 127 (33), 11851-11862
- https://doi.org/10.1021/ja052947c
Abstract
Imaging oxygen in 3D with submicron spatial resolution can be made possible by combining phosphorescence quenching technique with multiphoton laser scanning microscopy. Because Pt and Pd porphyrin-based phosphorescent dyes, traditionally used as phosphors in biological oxygen measurements, exhibit extremely low two-photon absorption (2PA) cross-sections, we designed a nanosensor for oxygen, in which a 2P absorbing antenna is coupled to a metalloporphyrin core via intramolecular energy transfer (ET) with the purpose of amplifying the 2PA induced phosphorescence of the metalloporphyrin. The central component of the device is a polyfunctionalized Pt porphyrin, whose triplet state emission at ambient temperatures is strong, occurs in the near infrared and is sensitive to O2. The 2PA chromophores are chosen in such a way that their absorption is maximal in the near infrared (NIR) window of tissue (e.g., 700−900 nm), while their fluorescence is overlapped with the absorption band(s) of the core metalloporphyrin, ensuring an efficient antenna-core resonance ET. The metalloporphyrin-antenna construct is embedded inside the protecting dendritic jacket, which isolates the core from interactions with biological macromolecules, controls diffusion of oxygen and makes the entire sensor water-soluble. Several Pt porphyrin-coumarin based sensors were synthesized and their photophyics studied to evaluate the proposed design.Keywords
This publication has 87 references indexed in Scilit:
- Hypoxia–ischemia in the immature brainJournal Of Experimental Biology, 2004
- Radio frequency continuous‐wave and time‐domain EPR imaging and Overhauser‐enhanced magnetic resonance imaging of small animals: instrumental developments and comparison of relative merits for functional imagingNMR in Biomedicine, 2004
- Excitation Energy Transfer in Branched Dendritic Macromolecules at Low (4 K) TemperaturesJournal of the American Chemical Society, 2003
- Fluorescence Resonance Energy Transfer in a Novel Two-Photon Absorbing SystemJournal of the American Chemical Society, 2003
- Mechanisms of Hypoxic Neurodegeneration in the Developing BrainThe Neuroscientist, 2002
- Phosphorescent Pd Porphyrin−Dendrimers: Tuning Core Accessibility by Varying the Hydrophobicity of the Dendritic MatrixMacromolecules, 2002
- Simulations of energy funneling and time- and frequency-gated fluorescence in dendrimersThe Journal of Chemical Physics, 2001
- Near-Infrared Two-Photon Excitation of Protoporphyrin IX: Photodynamics and Photoproduct Generation¶Photochemistry and Photobiology, 2000
- Supramolecular dendrimers with a [Ru(bpy)3]2+ core and naphthyl peripheral unitsNew Journal of Chemistry, 1999
- Atomic silver fluorescent probe of metal-support interactions in zeolitesThe Journal of Physical Chemistry, 1985