The Establishment And Application Of Photochemical Detecting Platform To Two Types Environmental Toxic Substances And Their Related Degradation Research

Organophosphorus derivatives(OPs)and boron trifluoride(BF3)are common environmental poisons.Abuse and illegal discharge have caused serious threats to the ecological environment and people’s health.The traditional detection methods of environmental toxicants generally rely on large instruments,which are difficult to meet the requirements of on-site detection due to complex operation and high cost.Therefore,the establishment of portable platforms with high stability,rapid response and low cost is of great significance for the level monitoring and degradation of OPs and BF3.In this paper,a series of responsive small molecule probes and composite nanomaterials were designed and synthesized,which were used to detect OPs and BF3 rapidly and degradate OPs using hydrogel,test paper,cotton fabric as carriers.The main contents of this paper were as follows:1.A novel molecular NH2-CA with AIEE properties was designed and synthesized,and combined with "covalent assembly" strategy to detect DCNP in solution and gas phase.NH2-CA showed good linearity(R2=0.9971)and high sensitivity(LOD=1.28 nM)in the determination of liquid DCNP in acetonitrile solution.At the same time,NH2-CA loaded retest strips were combined with smart phones to detect DCNP in the gaseous state and under solid state,with the lowest detection limit of 0.33ppm.2.SA@UiO-66-NH2@PAMAM complex hydrogel was designed and synthesized for degradation of organophosphorus nerve agents and visual monitoring of sarin(GB)degradation.The active sites of Zr-OH-Zr,-NH2 buffer base,and liquid water required for degradation were contained in SA@UiO-66NH2@PAMAM.Rapid degradation of nerve agents can be achieved in a hydrogel catalyst system with a half-life of only 7 min without any additional auxiliary substances.SA@UiO-66-NH2@PAMAM could also be easily processed into cotton fabric to form a recyclable flexible cotton device of SA@UiO-66NH2@PAMAM@Cotton.By adding the indicator of 4-nitro-(dimethyl-tert-butyl)silica ether(P-NSE)to the composite hydrogel system to form a new Gel-1,the degradation changes could be achieved when yellow nitrophenol(P-NP)was produced in gel through the monitoring hydrolysis of nerve agent GB.Thus,the integrative multifunctional hydrogel of Gel-1 with a smartphone as a portable platform also realized degradation monitoring of GB under visible light.3.A strategy for detecting trace amount OPs was designed and developed by combining auto-inductive cascade signal amplification approach and a sensitization behavior of Tb3+hydrogel.Acetylcholinesterase(AChE)catalyzed the hydrolysis of acetylcholine(ATCh)to produce thio-choline(TCh),which reacted with initiator CA-PhSH to trigger self-induction cascade signal amplification.Finally,PhSH produced by cascade amplification could react with presensitizer to produce sensitizer DHN,which sensitized Tb3+hydrogel luminescence.The entire signal amplification process and the luminescence of Tb3+hydrogels were inhibited when OPs was present.The purpose of OPs detection was realized by the relationship between luminescence intensity and OPs concentration.Due to the promotion by CA-PhSH,the process of auto-inductive cascade and luminescence response could be completed only in 3 min and 5 min respectively,which had greatly improved the efficiency of OPs detection.The lowest detection limit of BK@Tb3+/hydrogel platform with the auto-inductive cascade approach for OPs was only 0.39 nM.In addition,a portable smartphone system had also been developed with this hydrogel platform and had successfully applied to detect OPs in vegetable,fruit samples and accurately monitor the degradation process of OPs in cabbage leaves.4.Organophosphorus levels in poisoned serum were evaluated using ZIF-8 nanoparticles functionalized by oxime group and enzyme activation regeneration strategy.ZIF-8-1 and ZIF-8-2 were synthesized from Oxime-1 and Oxime-2 coligands by the "deletion linker" defect strategy.ZIF-8-2 exhibited excellent performance than that of ZIF-8-1 in activating and regenerating the activity of butyrylcholinesterase(BChE)suppressed by demeton-S-methyl(DSM)and could rapidly detoxify for DSM in poisoned serum samples within 24 min.Additionally,the synthesized fluorescence probe of IND-BChE could be used for the detection of BChE in a lower LOD of 0.63 mU/mL BChE.By difference between fluorescent intensity of IND-BChE with and without ZIF-8-2,a highly linear relationship of IND-BChE with DSM concentration had gotten(R2=0.9889),and the LOD was 0.036 μM.While,an intelligent detection platform of ZIF-8-2@INDBChE@agarose hydrogel combined with smartphone had formed for the point-ofcare testing of DSM which poisoned in serum samples.Unlike other detection methods of never agent,this assay firstly was combined NMOFs reactivator for detoxification,detection of BChE enzyme activity,and then quantification of OP never agents.5.A fluorescence-colorimetric dual mode probe(BK-Cy)was designed,synthesized and grafted to cotton fabric for the detection of BF3 in solution and gas.The diphenylamine group in the middle of BK-Cy skeleton structure reacted with BF3,and the intramolecular charge transfer(ICT)was blocked,resulting in obvious changes in the UV absorption intensity and fluorescence intensity.BK-Cy had the advantages of fast response(<1 min),low detection limit(1.73 nM)and high selectivity.At the same time,a portable detection platform was formed by assembling smart phones with BK-Cy@Cotton,and the color change of BKCy@Cotton was recognized by color recognition APP,so as to achieve the purpose of quantitative detection of BF3 gas.