DNA-Modified Electrochemiluminescent Tris(4,4’-Dicarboxylicacid-2,2’-Bipyridyl)Ruthenium(II) Dichloride and Assistant DNA-Modified Carbon Nitride Quantum Dots for Hg²⁺ Detection

Abstract

Accurate determination of hazardous Hg2+ is particularly essential for the environment safety and human health. In this work, using Hg2+ as a bridge for the electrochemiluminescence (ECL) reagent and the corresponding coreactant, a new type of self-enhanced ECL nanomaterial was simply and controllably prepared for the first time. In detail, tris (4,4′-dicarboxylicacid-2,2′-bipyridyl) ruthenium­(II) dichloride modified with DNA1 (Ru-DNA1) and graphite-like carbon nitride quantum dots linked with DNA2 (QDs-DNA2) were used as the ECL reagent and coreactant, respectively. In the presence of Hg2+, they could be integrated together to form a self-enhanced ECL nanomaterial (Ru-DNA1-Hg2+-QDs-DNA2) via the T-Hg2+-T duplex structure. The ECL signal strength was positively proportional to the concentration of Hg2+. On this basis, sensitive and selective detection of Hg2+ could be achieved by simply modifying the ECL nanomaterial on the electrode surface. Under the optimal experimental conditions, the proposed sensing strategy expressed a superior linear relation with Hg2+ concentration from 10 fM to 1 nM. Moreover, a low detection limit of 3.3 fM with outstanding selectivity, repeatability, and stability for Hg2+ analysis was obtained. In addition, the proposed sensing strategy exhibited reasonable accuracy for real sample assay compared with the atomic fluorescence spectrometry method. From this work, it is suggested that by programming the analytes and the corresponding recognition element, other analytes might also be sensitively and selectively detected using the proposed method.

Electrochemiluminescence of Carbon‐based Quantum Dots: Synthesis, Mechanism and Application in Heavy Metal Ions Detection

“…Therefore, the change of ECL intensity showed a good linear relationship with Pb 2 + concentration from 5.0 × 10 À 11 to 1.0 × 10 À 6 M. Kratochvílova found that the T-Hg 2 + -T structure was highly stable and could accelerate the charge transport rate in DNA [103]. To further improve the performance, Li et al prepared a new type of self-enhanced ECL nanomaterial (Ru-DNA1-Hg 2 + -DNA2-QDs) by combining the luminophore and the co-reactant into material through the T-Hg 2 + -T structure [104]. As shown in Figure 16, the ECL signal of self-reinforcing material formed by T-Hg 2 + -T is obviously enhanced, and the ECL signal of Ru-DNA1-Hg 2 + -QDs-DNA2 could be controllably regulated by…”

“…To further improve the performance, Li et al. prepared a new type of self‐enhanced ECL nanomaterial (Ru‐DNA1‐Hg 2+ ‐DNA2‐QDs) by combining the luminophore and the co‐reactant into material through the T‐Hg 2+ ‐T structure [104]. As shown in Figure 16, the ECL signal of self‐reinforcing material formed by T‐Hg 2+ ‐T is obviously enhanced, and the ECL signal of Ru‐DNA1‐Hg 2+ ‐QDs‐DNA2 could be controllably regulated by adjusting the Hg 2+ concentration.…”

Achieving Ultrasensitive Point-of-Care Assay for Mercury Ions with a Triple-Mode Strategy Based on the Mercury-Triggered Dual-Enzyme Mimetic Activities of Au/WO3 Hierarchical Hollow Nanoflowers

“…As one of the most hazardous and notorious contaminants, mercury has caught particular attention of the researchers worldwide because of its high toxicity to humans and the ecosystem. − Among the different states of mercury, mercuric ions (Hg 2+ ) are the most stable form, which can be dissolved in water leading to contamination of aquatic ecosystems. − Mercuric ions are non-biodegradable and can be accumulated in the biological body through the food chain. Owing to the strong binding capacity of Hg 2+ for sulfhydryl groups in proteins and enzymes, excessive mercury exposure will result in several serious illnesses such as kidney damage, respiratory failure, acrodynia, nervous disorder, Hunter–Russell syndrome, and so forth. − Hence, it is imperative to resolve the Hg­(II) pollution without delay.…”

Rapid and sensitive detection of Hg2+ with a SERS-enhanced lateral flow strip

“…In addition, electrochemical techniques are also widely used in DNA probe-based mercury sensors. [21][22][23] Usually, the electrode is easily modified with nucleic acid due to its excellent biocompatibility, and the sensing of the Hg 2+ can be realized based on the target-induced formation of T-Hg 2+ -T mismatch structures on the interface. 24 Although this kind of method has satisfactory sensitivity and selectivity, for practical on-site detection applications, ensuring repeatability and stability remains a challenge.…”