Novel Organic Frameworks For Detecting Nitrated Polycyclic Aromatic Hydrocarbons And Removing Of Chloroquine Phosphate In Food Samples

Nitrated polycyclic aromatic hydrocarbons(N-PAHs)are the persistent organic pollutants,found in food(meat,coffee,and water)and the environment(soil and PM_2.5).Among them,Chloroquine phosphate(CQ),a drug used for treaing COVID-19,is widely present in natural water sources.Owing to the high toxicity,persistence,and bioaccumulation of pollutants,their accumulation in organisms and drug-resistant bacteria ultimately poses a threat to human health via the food chain.Unfortunately,real samples containing these pollutants have complex matrices,which hinder the direct detection of trace N-PAHs.Therefore,developing a simple and sensitive detection method is desirable.Moreover,a simple and efficient method for removing CQ from water,which has been only accomplished to date via degradation,is required.In this work,two novel functional materials(Fe₃O₄@TAPT–DMTA–COF and BPT–DMB–CMP)were synthesized.Fe₃O₄@TAPT–DMTA–COF was used as an adsorbent to establish a new method for detecting N-PAHs in food and water samples as adsorbents using magnetic solid phase extraction(MSPE).BPT–DMB–CMP was used as a new adsorbent to removal CQ from water.The applicability and feasibility of these methods were verified,and the adsorption mechanism was investigated.The main results are as follows:A new magnetic covalent organic framework(COF)(Fe₃O₄@TAPT-DMTA-COF)was synthesized as an adsorbent for enriching and detecting five types of N-PAHs from food and water using gas chromatography-tandem mass spectrometry(GC–MS/MS).The reaction time for synthesizing magnetic COF was optimized.Characterizing the new material revealed a novel crystalline magnetic COF with a grapevine structure instead of a single core-shell structure,which improved the thermodynamic and kinetic properties of the material.Therefore,compared with the previously reported magnetic COFs,Fe₃O₄@TAPT–DMTA–COF possessed high crystallinity,large surface area,saturation magnetization,and remarkable chemical stability.The MSPE conditions(extraction time,the dosage of adsorbent,Na Cl%,and extraction temperature)were optimized using the response surface method,the eluent solvents were also optimized using single factor analysis.Five types of N-PAHs were detected using a method based on MSPE–GC–MS/MS.The linear range of the five N-PAHs was 10–5000 ng·L^-1 with good correlation coefficient(R~2?0.9929).The limits of detection were in the range of 1.43–17.24 ng·L^-1.The magnetic Fe₃O₄@TAPT–DMTA–COF–based MSPE method could effectively detect N-PAHs in food(coffee,roasted meat and smoked sausages)and water(Heihu spring)samples.The recoveries were 61.0%–112.8%.This research will provide the new method for the COF with high crystallinity and network structure.And it will also provide a new sample preparation method(MSPE)for decting N-PAHs in food and environment.A new conjugated microporous polymer(CMP)(BPT–DMB–CMP)was synthesized as an adsorbent to remove CQ from water.The morphology and physical property of this material were characterized using XPS,FTIR,SEM,BET,and Zeta potential analyses.The experimental results showed that the material possessed high adsorption capacity(334.70mg·g^-1)for CQ.The fastest equilibrium time was 1 h.At p H neutral(p H=6),the best adsorption effect was acheived.From the viewpoint of econoy,0.5 g·L^-1 was considered the optimal parameter.The kinetic curves and adsorption isotherms followed the mixed and Liu models,respectively.Furthermore,the material exhibited excellent reusability.The adsorption mechanism was explored by performing theoretical simulations and XPS.This study provides a new method with high adsorption capacity for removing CQ from water.