Keys for Unlocking Photolabile Metal‐Containing Cages

Abstract

Photolabile metal-containing cages are metal complexes that undergo a change in coordination environment upon exposure to light of an appropriate wavelength. The light-responsive functionality can either be a component of the encapsulating ligand or a property of the metal complex itself. The altered coordination properties of light-responsive complexes can result in release of the coordinated metal ion into its surroundings, a differential reactivity of the metal center, or the liberation of a reactive molecule that had been passivated by binding to the metal center. These triggerable agents can be useful tools for manipulating the bioavailability of metals or their coordinating ligands in order to study biological pathways or for potential therapeutic purposes.

Sensitization of NO‐Releasing Ruthenium Complexes to Visible Light

“…[8][9][10] In particular,t he field of metal nitrosyl and carbonyl complexes releasing NO or CO, respectively,u pon exposure to low-intensity light of various wavelengths is rapidlye volving. [7,[11][12][13][14][15][16] Current research focuseso n the optimization of NO-and CO-releasing molecules (NORMs and CORMs) with respectt ot heir biocompatibility,s olubility, and drug-targeting strategies. [17] Photoreactivity in therapeutically accessible spectral regions( 600-900nm) includes the improvement of two-photon absorption properties or NIR-photosensitivity,asw ell.…”

Photochemical delivery of nitric oxide

“…Furthermore, since the amount of photochemical reaction is a function of the quantity of light delivered to the desired target, this allows one also to define the dosage of the release. Although the present manuscript is focused largely upon our own studies, it should be noted that there is a growing interest in applying photochemical methods to the uncaging of NO [7][8][9][10][11][12] and CO [5,[13][14] as well as other bioregulators [15].…”

Light‐Controlled Release and Uptake of Zinc Ions in Solution by a Photochromic Terthiazole‐Based Ligand

“…Curiously, reports on photo‐switching of the stability of a metal complex, thus the concentration of a given metal ion in solution, are rare and limited mainly to alkali or alkaline earth metal complexes, by using suitable crown‐ethers or aza‐crown‐ether functionalized diarylethenes . By offering a convenient and non‐invasive way to reversibly photo‐modulate the concentration of a given metal ion in solution, such metal complexes are of interest for a broad range of potential applications, particularly in biology where a strict regulation of the concentration of different metals is crucial for the healthy functioning of cells …”