Electrochemiluminescence of a Vinyl-Functionalized Ruthenium Complex and Its Monolayer Formed through the Photoinduced Thiol-Ene Click Reaction

Electrochemiluminescence of iridium(III)/ruthenium(II) complexes with naphthyl tags in solutions and host-guest thin films

Herein we report electrochemiluminescence (ECL) generation from three new iridium(III)/ruthenium(II) (Ir(III)/Ru(II)) complexes with naphthyl (nap) tags in solutions and host-guest thin films. In comparison with its parent structure, the addition of a nap tag to [4-(2-naphthalenyl)-1,10-phenanthroline]bis(2,2'-bipyridine)ruthenium(II) results in a 6.1-fold enhancement in the ECL efficiency. Moreover, the nap tag enables the non-covalent immobilization of Ir(III)/Ru(II) complexes via host-guest interactions. Therefore, a molecular thin film was constructed by hydrophobic effects between the cavity of β-cyclodextrin and the nap tags, which emits stable and strong ECL emission in the presence of tri-n-propylamine (TPrA). These results give a mechanistic insight into ECL generation from (Ir(III)/Ru(II)) complexes with host-guest recognition tags and may help in the development of host-guest thin film-based ECL sensors.

Highly Active Electrochemiluminescence of Ruthenium Complex Co-assembled Chalcogenide Nanoclusters and the Application for Label-Free Detection of Alkaline Phosphatase

Rational design of electrochemiluminescence (ECL) reagents is essential for the development of ECL biosensors with superior performances. In this work, the assembly of tris(1,10-phenanthroline)ruthenium(II) [Ru(phen)₃²⁺] and tetrahedral chalcogenide nanoclusters of [Cd₃₂S₁₄(SC₆H₅)₃₈]^2- in the formation of complex nanoclusters (CdS-Ru) was developed, in which Ru(phen)₃²⁺ was uniformly encapsulated and dispersed at a molecular level in the chalcogenide nanocluster via multiple noncovalent interactions. It was observed that the promoted ECL emission was realized by the charge transfer between the tetrahedral CdS nanocluster and Ru(phen)₃²⁺ by the formation of the assembly complex, which was elucidated by cyclic voltammetry curves, ECL-potential curves, and in situ dynamic ECL spectra. Taking advantages of the facile charge transfer in the open framework CdS-Ru, a high ECL efficiency has been achieved with remarkable stability. Moreover, a solid-state ECL sensor based on the CdS-Ru modified electrode was fabricated for label-free detection of alkaline phosphatase (ALP) activity with a detection limit as low as 0.35 U/L and superior reproducibility. This solid-state ECL sensor also displayed favorable selectivity among various interferences and was applied for ALP activity analysis in human serum samples. These results implicated the potential applications of CdS-Ru for sensitive ECL analysis in complicated reaction systems and enlightened the rational design for self-enhanced and highly efficient ECL materials.

Nanocage-confined electrochemiluminescence for the detection of dopamine released from living cells

Herein we report an electrochemiluminescent nanocage array (ENA) in which luminophores are physically confined. The ENA can function as a solid sensor for the detection of dopamine released from living cells on the basis of its quenching effect on the ECL signal.