Rapid Detection Of 3-MCPD Using The Prepared Paper-Based Molecularly Imprinted And Fluorescence Response

BackgroundChloropropanol is one of the by-products of acid hydrolyzed vegetable protein?HVPs?,epoxy resin,epoxy chloropropane and so on.The small amount of HVPs added in the preparation of soy sauce and oyster sauce is the primary source of chloropropanol in food^[2,4],which has seriously threatened the health of consumers.Chloropropanol,which is transferred from epoxy resin to food,is another source of chloropropanol in food.However,there is still no efficient,convenient and fast method to detect chloropropanol.Therefore,this study explored the preparation of paper based imprinting composites with high selectivity and convenience of molecular imprinting by controllable synthesis of molecular imprinting on paper.MethodThis study 3-MCPD as template molecule,4-vinyl benzene boric acid as functional monomer,using reversible addition-breaking chain transfer radical polymerization technology,the paper base on construction of functional molecular imprinting hole3-MCPD controllable and specificity recognition,as a highly selective paper-based molecularly imprinted composite materials.The optimum adsorption time,adsorption performance and adsorption capacity of paper-based composites were evaluated by static adsorption experiment and dynamic adsorption experiment.Then introduce the preparation of citric acid carbon quantum dots paper-based molecularly imprinted composite material,and by studying the paper adsorption performance of molecularly imprinted composite materials,further analysis of the controllable polymerization and specific recognition mechanism.Finally,a method has been established to detect the content of 3-MCPD in soy sauce and other foods quickly,conveniently,accurately,cheaply and sensitively.Result1.Reachs via optimization the preparation which has the function of specific identification of 3-MCPD optimal scheme for paper-based composite material,with 0.2mmol 3-MCPD as template molecule,0.2 mmol 4-vinyl benzene boric acid as functional monomer,2.0 mmol EGDMA as crosslinking agent,to join the 4.0 mL DMF solvents,choose according to the fluorescence detection of 5.0 mg/mL solution concentration of carbon quantum dots as fluorescent stain.The paper matrix composite obtained after washing for 100 min has the best adsorption performance for 3-MCPD,reaching 9.98mg/g.2.By scanning electron microscope analysis and infrared spectroscopy,the paper matrix composite was characterized and analyzed,and it was proved that the synthetic imprinted holes had been successfully linked on the fiber paper surface.In 3-MCPD solution concentration of 2.0 mg/L,paper-based composite material of MIPs and NIPs equilibrium adsorption capacity,were 4.24 mg/g and 0.72 mg/g,using Langmuir adsorption isotherm model to calculate the paper-based composite material of imprinting index is 1.77,showed the MIPs to 3-MCPD strong adsorption ability.By using Scatchard method to analyze the binding site information of target molecules in paper based imprinting materials,it is proved that there are two different binding sites between MIPs and 3-mcpd.The selective experiment shows that it has high selective adsorption performance to target molecule 3-MCPD.3.A fast detection method with a standard curve range of 0.2-6.0 mg/L and a good linear curve with a detection limit of 0.16 mg/L was established using paper-based composite materials.Through the test method of 6 kinds of common commercial soy sauce products for testing,neither has 3-MCPD residue detection,analysis of the sample testing the standard addition recovery rate at the same time,add a scalar in 0.5 mg/L to 2.0 mg/L,standard addition recovery rate range from 83.4%to 109.7%,that test results are to be believed,and six kinds of soy sauce is indeed a brew soy sauce.Conclusion1.The best paper-based imprinted composite material preparation scheme has been determined by gradual optimization.2.Confirm that the molecular imprinting is successfully prepared on the paper base,MIPs has the binding site of 3-mcpd specific adsorption,and the adsorption capacity is stronger than the non-specific binding site,MIPs has a strong selective adsorption for3-MCPD.3.Fluorescent paper base molecularly imprinted composite material can be used for3-MCPD residues in soy sauce and soy sauce products of fast,convenient and cheap screening tests,the method of the minimum detection limit of 0.16 mg/L,detection range in 0.2 mg/L to 6.0 mg/L,can get after 10 min adsorption test results,add a scalar in 0.5mg/L to 2.0 mg/L,standard addition recovery rate range from 83.4%to 109.7%,so this method can be used for field test for rapid screening for reference.