Fluorescent Organometallic Sensors for the Detection of Chemical‐Warfare‐Agent Mimics

Abstract

Mixing and matching: The highly selective detection of chemical‐warfare‐agent mimics can be achieved by judicious combination of carefully designed fluorescent ligands and metal ions. Designed sensor arrays of these multimetal/multiligand systems represent a modular and versatile approach for the detection of organophosphates and other analytes.

Luminescent Mechanochromic Sensors Based on Poly(vinylidene fluoride) and Excimer‐Forming p‐Phenylene Vinylene Dyes

“…Fueled by academic curiosity and the potential for use in applications that range from security features, [1] lightemitting diodes, [2] lasers, [3] to chemical sensors, [4] the development of luminogenic polymers [5] is attracting much interest in laboratories around the world. We recently developed a new family of stimuli-responsive luminogenic polymers, which change their emission color upon exposure to a range of stimuli.…”

Converting an intensity-based sensor to a ratiometric sensor: luminescence colour switching of an Ir/Eu dyad upon binding of a V-series chemical warfare agent simulant

“…Titration of DMMP into a solution of Eu(hfac) 3 An analogous titration of Et 3 N into Eu(hfac) 3 (H 2 O) 2 generated a steady decrease in Eu(III) luminescence, consistent with the amine acting as a quencher of the Eu(III) excited state (Fig. 1b).…”

“…Importantly, the excitation wavelength used for luminescence measurements on Ir•L•Eu is 395 nm -a region where the Ir chromophore absorbs, but free Eu(hfac) 3 (H 2 O) 2 and Eu(hfac) 3 (VO) do not. Thus, in the evolving luminescence spectra, the only E u -based emission that is present is sensitised emission from Ir→Eu energy-transfer in the intact dyad; Eu(hfac) 3 (H 2 O) 2 a n d E u ( h f a c ) 3 (Fig. 4).…”

“…This might be an increase in luminescence intensity if water ligands (which can have a limited quenching effect) are displaced from the coordination sphere of the metal ion; 2 o r a d e c r e a s e i n i n t e n s i t y i f a sensitising antenna ligand is displaced. 3 In some cases changes in relative intensity between different lines in the Eu(III) emission spectrum have provided a basis for ratiometric sensing. 4 However, analysis of these generally requires spectrophotometric measurements as the spectral changes involved are not always obvious to the naked eye in the form of a clear colour change.…”

Chromogenic detection of nerve agent mimics

“…2 Reported paradigms involve PET-based fluorescent probes, 3 colorimetric probes with oximate-containing derivatives, 4 molecular imprinting polymers, 5 nanoparticles, 6 carbon nanotubes, 7 porous silicon 8 or displacement-like assays. 9 Most of these reported protocols rely on fluorescence changes and as far as we know chromogenic systems for nerve agent detection in aqueous solution or as vapour are rare. Some reported colorimetric examples employ enzymatic methods and are based on the inhibition of the activity of the enzyme acetylcholine esterase.…”