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

Abstract

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) 3 2+ ] and tetrahedral chalcogenide nanoclusters of [Cd 32 S 14 (SC 6 H 5 ) 38 ] 2− in the formation of complex nanoclusters (CdS−Ru) was developed, in which Ru(phen) 3 2+ 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.

Water Activation for Boosting Electrochemiluminescence

“…Phenyl phosphate disodium salt (PPNa) can be selectively hydrolyzed into phenol with the presence of ALP. Then, phenol could be electrochemically oxidized to a nonconductive polyphenol film deposited on the electrode surface [28] . As a result, the charge transfer resistance ( R ct ) would be increased and the ECL intensity would be suppressed.…”

“…Then, phenol could be electrochemically oxidized to a nonconductive polyphenol film deposited on the electrode surface. [28] As a result, the charge transfer resistance (R ct ) would be increased and the ECL intensity would be suppressed. As shown in Figure S14, the EIS measurements were performed.…”

Addressing the Origin of Single-Atom-Activated Supports Monitored by Electrochemiluminescence

“…The ECL spectra were measured for Ru SA/NiFe-LDH and NiFe-LDH, and a maximum emission wavelength of around 425 nm can be acquired (Figure S1). Such an emission could be ascribed to the typical ECL emissions of luminol rather than those from the Ru-complex at 625 nm. − In addition, the reproducibility and long-term durability of the ECL signals have been implemented. The ECL signals increased gradually to a stable plateau for both NiFe-LDH and Ru SA/NiFe-LDH due to the accumulation of reactive oxygen species (Figure S2).…”

Metal Nanoclusters in Point-of-Care Sensing and Biosensing Applications

“…A high ECL was obtained with superior stability, which was utilized as a point-of-care framework for ALP in the following (Figure ). The designed platform presented a nice LOD of 0.35 U/L and high reproducibility and stability …”

“…Schematic of the preparation of a ECL sensor based on [Cd 32 S1 4 (SC 6 H 5 ) 38 ] 2– NCs for ALP detection. Reproduced from ref . Copyright 2021, American Chemical Society.…”