Visualized electrochemiluminescence iodine sensor based on polymer dots with Co-reactive group for real-time monitoring system.

Trace iodine (I 2) radioisotopes are commonly regarded as an indicator in nuclear security early warnings. Herein, we develop a visualized I 2 real-time monitoring system using electrochemiluminescence (ECL) imaging technology for the first time. In detail, the polymers based on poly [(9,9-dioctylfluorene-alkenyl-2,7-diyl)- alt - co -(1,4-benzo-{2,1',3}-thiadiazole)] are synthesized for iodine detection. An ultra-low limit of detection (0.01 ppt) to iodine can be achieved by adding the modification ratio of tertiary amine onto PFBT as a co-reactive group, which is the lowest detection limit in known iodine vapor sensors. This result can be attributed to the co-reactive group poisoning response mechanism. Considering to the strong ECL behavior of this polymer dots, P-3 Pdots with ultra-low detection limit for iodine is combined with ECL imaging technology to realize the visualized rapid I 2 vapor response with high selectivity. ECL imaging component based on ITO electrode can make iodine monitoring system more convenient and suitable for real-time detection in early warning of nuclear emergency. The detection result cannot be affected by vapor of organic compounds, humidity and temperature, indicating a good selectivity to iodine. This work provides a strategy for nuclear emergency early warning, showing its significance in environmental and nuclear security fields. [Display omitted] • A real-time visualized monitoring system for trace I 2 is developed by ECL technology. • An ultra-low detection limit of 0.01 ppt is obtained in iodine detection. • Co-reactant group poisoning mechanism is proposed for high detection sensitivity. • The good selectivity is obtained for iodine with different VOCs and humidity. [ABSTRACT FROM AUTHOR]