The Synthesis And Application Of Molecularly Imprinted Polymers Of Vanillin

Vanillin is an important flavor chemical which is widely used in food,beverage, perfume and medicine.As natural vanillin is not far enough to meet people's need and man-synthesized one has many problems like safety and limited application,research of biosyntheiszed vanillin attracts lots of scientists' interests.In the extraction procedure of vanillin,molecular imprinted technology can effectively reduce toxicity and anti-restraining to microorganism from vanillin,and increase the productive rate,conversion and purity of vanillin,which has great significance of theory and practical application.In this paper,we focused on the synthesis and application of vanillin molecular imprinted polymers.Based on the structure of vanillin,twelve functional monomers were synthesized and polymerized respectively.Their property of absorption were tested.The results were listed as follows:The functional monomer with the best performance: N-(4-oxo-2-thioxothiazolidin-3-yl) acrylamide The best cross-linker:EDMA,which competed with other 5 kinds of cross-linkers:pentaerythritoltrimethylacrylate, trimethylolpropanedimethacrylate,(glycerindimethyl)methyl acrylate,divinyl benzene, 3,5-bis(acrylamido)aminobenzoic.The best rate of vanillin,N-(4-oxo-2-thioxotHiazolidin-3-yl)acrylamide and EDMA was 1:5:25,which was achieved by testing the performance of the molecularly imprinted polymers which were individually synthesized with different rate among vanillin,N-(4-oxo-2-thioxothiazolidin-3-yl)acrylamide and EDMA.The best ignition agent is azobisisobutyronitrile,which is compared with other two agents:benzoyl Peroxide and peroxysulphuric acid.The best solvent is chloroform,compared with methylbenzene and acetonitrile.Then the optimized absorption rate of MIPs-d to vanillin whose concentration is 10^-4mol/L is up to 96.86%.The MIPs-d was applied in the simulation fermented broth to get the best absorption condition:pH value of the liquor is 7.0,the addition mass of the MIPs-d is 1.0g,the temperature of the solution is 50℃,and the absorption time is 1 hour.And the absorption rate of MIPs-d to vanillin in such conditions is up to 93.73%.