Ultrafast Sulfur Mustard Simulant Gas Fluorescent Chemosensors Based on Triazole AIEE Material with High Selectivity and Sensitivity at Room Temperature

Abstract

Herein, a novel blue aggregation-induced enhanced emission (AIEE) material 4-N-(naphthalen-l-yl)-3,5-bis­(4-N-phenyl-1-naphthylamine)­phenyl-4H-1,2,4-triazole (NDTAZ) is developed and used as a fluorescent chemosensor for sulfur mustard (SM) simulant 2-chloroethyl ethyl sulfide (2-CEES) vapor. The NDTAZ chemosensor is designed by introducing an electron-donating N-phenyl-1-naphthylamine group at 3 and 5 position of 4H-1,2,4-triazole (TAZ) to enhance the nucleophilicity of the TAZ group, and a naphthalene ring is connected to 4 position of the TAZ group to construct an AIEE molecule. The NDTAZ films show extraordinary stability and then are further used as reliable and portable fluorescent chemosensors. Upon exposure to 2-CEES vapor, the NDTAZ chemosensor exhibits an instantaneous fluorescence response (not more than 1 s). What should be noted is that this fluorescent chemosensor realizes the visualized detection of fluorescent color change from blue to green at “room temperature”, which is rarely reported. The limit of detection is estimated to be 0.55 ppm, which is below the AEGL-1 (0.6 ppm for 1 min) safety ceiling level to SM exposure. Moreover, the NDTAZ chemosensor shows high selectivity toward 2-CEES vapor over closely related substances, including alkylating agents, aryl halide compounds, sulphur-containing compounds, and nerve agent mimics. More impressively, the NDTAZ chemosensor demonstrates good recyclability by water treatment. Also, the sensing mechanism is adequately proved by using multiple experimental methods and theoretical calculation. In addition, the NDTAZ-based facile filter paper-constructed test strips are fabricated for real-time and on-spot detection of leaked 2-CEES gas specifically. Therefore, this fluorescent chemosensor with excellent sensing performance greatly advances the practical detection of SM species at room temperature.

Recent advances in aggregation-induced emission (AIE)-based chemosensors for the detection of organic small molecules

“…On another note, Zhang et al synthesized a blue fluorescence chemosensor ( D74 ) based on triazole, for the detection of mustard gas simulant 2-CEES. 415 The emission of a thin film of D74 changes from blue to green within 5 seconds when exposed to 2-CEES vapor. However, its emission can be readily reversed when soaked in water.…”

Designing one-dimensional covalent organic frameworks: novel post-synthetic modification on hydroxyl groups and ratiometric detection of chemical warfare agent mimics

“…Among them, sulfur mustard (SM), also referred to as the "king of poisons", 4 is a potent blistering agent that can cause severe cutaneous blisters, permanent blindness and even respiratory failure. 5,6 In 2017, SM was classied as a group 1 carcinogen by the International Agency for Research on Cancer of the World Health Organization. 7,8 Tabun is another kind of CWA, 9 which can trigger central nervous system paralysis, multiple organ failure, or instantaneous death of a living organism.…”

An in situ, reversible fluorescent paper sensor for selective detection of ambient CO2

“…Their applications include monitoring air quality, detecting hazardous gases, and clinical diagnosis. The target gases vary between volatile organic compounds 3 (VOCs), explosive gases, 4 highly-toxic gases, 5 and the other common gases, 6,7 depending on different scenarios. The analytical methods behind these sensors can be primarily divided into mass spectrometry, 8 electrochemical methods, 9 IR absorption, 10 and colorimetric/fluorescent methods.…”