The Synthesis And Application Of Fluorescence Probes For Mustard Gas And Phosgene

Chemical warfare agents are highly toxic chemical substances used to poison or kill the enemy’s military and civilian populations on a large scale in war,and have been used many times in wars and terrorist activities.On the other hand,some chemical warfare agents are common chemicals that are easily available and may be used by terrorists,posing a long-term threat to human life or national security.Therefore,developing fast and highly sensitive detection techniques such as fluorescent probes is particularly important.This article is dedicated to developing fluorescence detection methods for two chemical warfare agents:mustard gas and phosgene.The main researches are as follows:Chromone,as a fluorophore,has an excellent performance in constructing fluorescent probes.We have introduced the structure of julolidine and thiocarbonyl into chromones to construct a new fluorescent probe,PCS,which can achieve faster(within 90 seconds)and more sensitive(～nM)detection of SM(mustard gas)and CEES(2-Chloroethyl ethyl sulfide).In terms of stability,probes with thiocarbonyl as the recognition site have good storage stability and can be converted into highly active sensing species for SM detection in alkaline ethanol solution.In practical applications,the prepared test strip with PCS achieves sensitive(<5 ppm)and selective detection of CEES in the gas phase.In addition,simple and rapid detection of CEES-contaminated surfaces can be achieved by spraying the ethanol solution containing PCS and KOH.Naphthalimide is a fluorescent group whose photophysical properties are easy to control.We have developed a naphthalimide-based fluorescent probe NI-SH for the detection of mustard gas.The probe uses sulfhydryl as the recognition site,and the fluorescence opening response is clearly observed after the nucleophilic substitution reaction between sulfhydryl and CEES under alkaline conditions.The sensing system has a very low detection limit of 25 nM and good selectivity for CEES,which is expected to be applied to the actual detection of mustard gas.Subsequently,we obtained a fluorescent probe DHNI for detecting phosgene by attaching double hydroxyl group to the 4,5 positions of naphthalimide.The probe exhibits a fast(<2 s)and highly selective colorimetric and ratiometric fluorescence response to phosgene.This work provides a promising fluorescence detection method for phosgene in solutions.