Improved AIE-Active Probe with High Sensitivity for Accurate Uranyl Ion Monitoring in the Wild Using Portable Electrochemiluminescence System for Environmental Applications

The development of highly sensitive and selective uranyl ion (UO22+) probes has attracted significant attention owing to the threat to human health caused by high toxicity, radioactivity, and long half-life. Herein, the development of aggregation-induced emission (AIE) active polymer dots (Pdots) is described for an accurate UO22+ monitoring using a portable electrochemiluminescence (ECL) system. An AIE-active polymer containing tetraphenylethene and boron ketoiminate moieties is prepared into Pdots and modified with ssDNA to capture UO22+, which can amplify the ECL signal of the Pdots through a resonance energy transfer mechanism. This probe provides an ultralow detection limit of 10.6 pm/2.5 ppt, which is at least two orders of magnitude lower than the known UO22+ luminescent probes. Only UO22+ can provide an obvious ECL enhancement among the various metal ions, indicating the excellent selectivity of this probe. Furthermore, a portable ECL analyzer is designed to realize UO22+ measurements in the wild. The anodic ECL mechanism of UO22+ is discovered and ECL technology is first applied in monitoring radioactive substances. This study provides a novel strategy for the development of accurate UO2.2+ probes and a practical UO22+ monitoring method, indicating its potential application in the environmental and energy fields.

由于铀酰离子（UO₂²⁺）具有高毒性、放射性以及长半衰期，对人类健康构成威胁，因此高灵敏度和高选择性铀酰离子探针的开发受到了广泛关注。在此，我们描述了一种具有聚集诱导发光（AIE）活性的聚合物点（Pdots）的开发，用于通过便携式电化学发光（ECL）系统对UO₂²⁺进行精确监测。一种含有四苯乙烯和硼酮亚胺基团的AIE活性聚合物被制成Pdots，并通过单链DNA（ssDNA）修饰以捕获UO₂²⁺，它可以通过共振能量转移机制放大Pdots的ECL信号。该探针的检测限极低，为10.6皮摩尔/2.5万亿分之一，比已知的UO₂²⁺发光探针至少低两个数量级。在各种金属离子中，只有UO₂²⁺能使ECL信号显著增强，这表明该探针具有优异的选择性。此外，还设计了一种便携式ECL分析仪，以实现野外UO₂²⁺的测量。我们发现了UO₂²⁺的阳极ECL机制，并且首次将ECL技术应用于放射性物质的监测。这项研究为开发精确的UO₂²⁺探针提供了一种新策略，以及一种实用的UO₂²⁺监测方法，表明其在环境和能源领域具有潜在应用价值。