Preparation Of Poly(amine Siloxane)Based Molecularly Imprinted Polymers And Its Application In Decabromodiphenyl Ether Analysis

Polybrominated diphenyl ethers(PBDEs)are mostly used as flame retardants for industrial consumer products,and as a kind of persistant organic pullutants(POPs),PBDEs are hazardous when they are remaining in envirement.Therefore,the detection of PBDE is very important for us.At this stage,the detection methods such as chromatography-mass spectrometer(GC-MS),etc.,are not;portable,costly and time consumerble.By the introduction of molecularly imprinted polymer film as a sensitive identification element to the target substance,moleculary imprinted electrochemical sensor can quickly and easily detect the target with high affinity and selectivity.In this paper,decabrominated diphenyl ether(BDE-209)was chosed as the target substance for detection.The main research work is as follows:1.A silicone functional monomer(Bis-CPTES-BAPTMDS)bearing two amine groups has been successfully systhesized from y-chloropropyltrimethoxysilane(CPTES)and 1,3-bis(3-aminopropyl)tetramethyldisiloxane(BAPTMDS)via a nuclep hilic substitution reaction.The Bis-CPTES-BAPTMDS possesses two functional groups wihtin the main chain and six polymerble siloxane groups at end,which can polymerize via sol-gel and form polymeric network.The resultant was characterized by FTIR,1H NMR and MS,and the interaction between functional monomer and BDE-209 was determined by UV-Vis spectrophotometry.It was believed that the interaction between them was based on hydrogen bond,and the optimal ratio of Bis-CPTES-BAPTMDS to BDE-209 was 10:3.2.The molecular imprinted hybrid has been prepared by using Bis-CPTES-BAPTMDS as a functional monomer,tetraethyl orthosilicate(TEOS)as a crosslinker and BDE-209 as a template molecule via sol-gel approach The hybrid was applied on indium Tin oxide(ITO)electrode,resulting in molecularly imprinted electrochemical sensor(MCBE@ITO).The electrochemical properties of MCBE@ITO were tested by cyclic voltaimmetry and the elution method,pH,adsorption time and other conditions were optimized.The linear range of the sensor was 0-50 μM and the detection limit was 8.85 detected by differential voltammetry.In addition,the sensor can specifically recognize BDE-209,with good repeatability and stability.The recovery rate of soil samples was 95.7%-102%and the standard deviation was 1.9%一 3.5%.This study shows that the Molecular Imprinting sensor obtained can be used for the detection of decabromodiphenyl ether.3.The effects of various silane crosslinkers on the parameters of molecularly imprinted sensors have been studied.The MCBM@ ITO and MCBP@ITO were prepared by using methylethoxysilane and phenylethoxysilane as crosslinkers respectively,followed by further optimizing the ratio of crosslinker to functional monomer,adsorption time and other conditions for MCBP@ITO.It was obtained that the linear range of MCBP@ITO is 0-500 nM and the detection limit is 17.8 nM by differential voltammetry.In addition,the sensor can specifically recognize BDE-209,with good repeatability and stability.The recoveries of MCBP@ITO for soil samples are 96.3%～104.9%and the standard deviation is 2.0%～3.2%.The results show that MCBP@ITO has the highest sensitivity,lowest detection limit,narrowest linear range and strongest anti-interference ability among three sensors.It is believed that the crosslinker,which is one of the three elements of molecularly imprinted polymers,has a significant effect on the performance of the sensor.