Ratiometric Iridium(III) Complex-Based Phosphorescent Chemodosimeter for Hg²⁺ Applicable in Time-Resolved Luminescence Assay and Live Cell Imaging

Abstract

A novel iridium(III) complex-based probe Ir4-1 has been designed and synthesized conveniently by incorporating the chemodosimeter into phosphorescent luminophor, which displayed ratiometric luminescence change from yellowish-green to reddish-yellow only toward Hg(2+) ions in aqueous media via desulfurization and intramolecular cyclization with a broad pH range of 5-10. The phosphorescent chemodosimeter could eliminate effectively the signal interference from the short-lived fluorescent background, and the signal-to-noise ratio of the detection was improved distinctly by using time-resolved photoluminescence technique. Furthermore, the mechanism of phosphoresce change of the chemodosimeter was analyzed in detail by time-dependent density functional theory (TD-DFT) calculations, and the probe with long-wavelength emission could be applied to label cells and monitor intracellular Hg(2+) effectively by luminescence ratio imaging.

Mito-Specific Ratiometric Terbium(III)-Complex-Based Luminescent Probe for Accurate Detection of Endogenous Peroxynitrite by Time-Resolved Luminescence Assay

“…Both the reference and responsive dyes of many other probes are directly adsorbed into the mesoporous silica layer shell by physical absorption. These above probes all face a problem that the adsorbed dyes may be lost from the mesoporous silica . Compared with them, in TD-DC, the reference dye (Tb­(DPA) 3 ) is completely coated by the silica nanoparticle by the reverse microemulsion method (Scheme B).…”

Responsive ruthenium complex probe for phosphorescence and time-gated luminescence detection of bisulfite

“…[10][11][12][13] TGL technique has become a powerful tool in background-free detection because the short-lived autofluorescence can be effectively eliminated by introducing a delay time after pulse excitation. 10 To develop responsive probes for TGL detection, the analyterecognition units are normally incorporated with the luminophores that have long-lived emissions, such as transition metal complexes, [14][15][16][17] lanthanide chelates, 18 and very limited number of organic fluorescence dyes. 19,20 Among these luminophores, phosphorescent d 6 transition metal complexes, especially Ru(II) and Ir(III) complexes, have recently received increasing interests for the development of responsive probes.…”

Naked‐eye detection of Cu (II) and Fe (III) based on a Schiff Base Ruthenium complex with nicotinohydrazide

“…[ 25–29 ] Usually, the d 6 , d 8 , d 10 ‐electron structure transition metal complexes usually exhibit significant Stokes shifts, long‐lived phosphorescence lifetimes, emission‐wavelength covering the whole entire visible range, high luminescence efficiency. [ 30–35 ] Among these heavy‐metallic complexes, ruthenium complexes have successfully been applied in confocal luminescence imaging, [ 36 ] time‐resolved photo‐luminescence detection [ 37 ] and ions recognition. It is notably that fluorescent sensors, which depend on emission intensity or position change and ions recognition, may be extremely influenced by excitation power and detector sensitivity.…”