AIE-Based Fluorescent Nanosensors for Detection of Heavy Metal Ions

Abstract

AbstractHeavy metal pollution is a serious global environmental problem that causes irreversible damage to the ecological environment and harms the human health. It is clearly imminent to develop an efficient and simple method for detecting heavy metals in the environment. Aggregation-induced emission (AIE)-based nanomaterials are excellent as a sensing platform, which enables rapid detection of heavy metals with high sensitivity and selectivity in aqueous solution, overcoming the drawbacks of traditional sensors such as poor solubility in water, aggregation-caused quenching, and insufficient signal-to-noise ratio. Herein, we summarize the recent efforts to develop AIE-based nanosensors for detecting heavy metal ions (including mercury, lead, zinc, copper, cadmium, chromium, and arsenic) with a focus on the sensing materials and mechanisms. Organic nanoparticles, metallic nanoclusters or nanoparticles, metal-organic frameworks, hydrogen-bonded organic frameworks, carbon dots, and quantum dots have been applied in the construction of AIE-based nanosensors to achieve the trace analysis of heavy metal ions, acting more in a fluorescence enhancement or quenching behavior. Moreover, some ratiometric nanosensors based on coupling two or more nanomaterials have shown some superiorities in selectivity, sensitivity, and accuracy. Despite the report that AIE-based nanosensors exhibit sufficient sensitivity to detect heavy metal ions in aqueous environment, the insufficient selectivity and specificity affect the capability of specially sensing in complex matrices.KeywordsNanosensorAIEHeavy metalDetectionFluorescence