Synthesis Of Fluorescent Probe With AIE And Its Detection Of Amphetamine In Municipal Sewage

Methamphetamine（METH）,also known as"ice",is a stimulant psychotropic drug.It has become the most abused drug and has the potential to replace heroin.Therefore,strengthening the control of methamphetamine abuse is of great significance.Since drug use is usually illegal and scarce,it is difficult to obtain reliable drug use data with traditional detection and enrichment methods.Urban environmental sewage is considered to be highly diluted human urine and body fluids,which can indirectly reflect the abuse of drugs.Sewage detection technology is very important for anti-drug intelligence work,combating drug crimes and crime prevention.Therefore,in recent years,sewage epidemiological methods based on domestic sewage testing have shown great advantages in drug abuse investigations.Among the many detection methods,the use of fluorescent probes to detect drugs has become a research hotspot in the fields of chemistry,environmental science,life science,and medicine.Various fluorescent materials designed based on the principle of Aggregation-Induced Emission（AIE）are widely used in various detection fields.Among them,tetraphenylethylene（TPE）has easy modification and high fluorescence quantum yield,and is often used as a fluorescent group to be introduced into the design of fluorescence sensors.Based on this,we designed and synthesized a series of TPE-containing fluorescent composite materials for the detection of illegal drugs such as methamphetamine,and collected urban sewage from multiple sewage treatment plants in Dalian to enrich the methamphetamine in the sewage.The fluorescence detection provides new methods and technical support for the further development of rapid fluorescence detection for illegal drugs.The specific research content is as follows:1.Cyclodextrin has excellent solubilization ability,good binding ability with organic pollutants,etc.,making it favored by scholars from all walks of life in the field of detection.Therefore,we designed and synthesized TPE-2COOH with AIE characteristics,and then combined TPE-2COOH with cyclodextrin by chemical synthesis and grinding methods,and used hydrogen nuclear magnetic resonance（¹H NMR）and infrared spectroscopy（FT-IR）,Scanning electron microscopy（SEM）characterized the structure of TPE-2COOH and TPE-2COOH@γ-CD.Fluorescence spectroscopy and dynamic light scattering tests prove that TPE-2COOH@γ-CD has AIE characteristics in the H₂O-THF solvent system.It also has the advantages of good light stability,good p H stability,and large Stokes shift,which lays the foundation for the subsequent detection of methamphetamine.2.Next,we test the response of TPE-2COOH@γ-CD to methamphetamine.As the concentration of methamphetamine increases,fluorescence quenching occurs.The experimental results show that TPE-2COOH@γ-CD can quantitatively detect methamphetamine,and has the characteristics of fast response speed and wide linear range.The linear range of detection is 0.10-0.26 mg/m L,and the detection limit is0.0035 mg/m L.The detection mechanism is:the cyclodextrin in TPE-2COOH@γ-CD captures methamphetamine in the solution through size matching,because the host-guest interaction capability of methamphetamine and cyclodextrin is better than that of cyclodextrin and TPE-2COOH.Therefore,TPE-2COOH was replaced,which caused the quenching of fluorescence,thus realizing the detection of methamphetamine.3.Methamphetamine continuously enters urban sewage through different channels.In recent years,sewage epidemiological methods based on domestic sewage testing have shown great advantages in drug abuse investigations.However,the content of methamphetamine in urban sewage is very low,so it needs to be detected by adding standard after enrichment.Two types of sewage are selected from Dalian urban sewage for enrichment and standard addition.The recovery rate of methamphetamine in the sewage after adding the standard is between 96%-114%,and the standard deviation is 0.90%.Therefore,this method can be used for the detection of methamphetamine in municipal sewage.