Preparation And Characterization Of Bovine Serum Albumin Molecularly Imprinted Polymers On The Surface Of Mulit-Walled Carbon Nanotubes Using The Ionic Liquids As Funtional Monomers

Molecularly imprinted polymer (MIP) is a kind of synthetic polymeric adsorbent material, which has specific recognition ability for particular target molecules. The drawback of traditional embedding method can be eliminated and macromolecular substances can be imprinted on the surface of the solid substrate with surface molecular imprinting technique. In this work, the bull serum albumin (BSA) MIP was synthesized in the surface of carbon nanotubes (CNTs) by using acrylamide modified carbon nanotubes as substrate materials, BSA as temple molecules, ionic liquids as function monomers, and N,N’-methylene diacrylamide as cross-linking agent through the free radical polymerization and suface molecular imprinting technique. The conditions for the synthesis and adsorption experiments were optimized. The properties of the synthetic BSA MIPs, such as the molecular structure, surface area, surface morphology, thermal stability, adsorption kinetics and thermodynamics, selectivity, specificity and competivity, and reusability were characterized and evaluated comprehensively. The absorption abilities of the BSA MIP synthesized with different diameter of carbon nanotubes or different types of functional monomers were also studied in detail. The main results are as follows:1. The optimal synthesis conditions for the [AMIM][PF6]-mediated MIP are20mg BSA,100mg [AMIM][PF6],100mg NNMBA,30mL phosphate buffer and40mg acrylamide modified carbon nanotubes. The mass ratio of BSA to [AMIM][PF6] to NNMBA is1:5:5. The reaction solution was stirred for48h at room temperatures after removing oxygen by30minutes of nitrogen purging.2. The maximum adsorption amount of BSA is56.53mg/g and the imprinting factor is α=2.05on the synthetic [AMIM][PF6]-mediated MIP. The optimal pH for the adsorption of BSA is4.7. The BSA MIP has good thermal stability, specific selectivity, and good competitiveness and reusability. The adsorption capacity didn’t have an obvious decline after repeated use for several times. 3. The diameter of CNTs influences it’s dispersibility in reaction system. MIPs synthesized with <8nm or10～20nm CNTs have better adsorption capacity. The types of functional monomers have great influence on the mode and strength of interaction between target moleculars and MIP. MIPs synthesized with [AMIM][CF3SO3] or [AMIM][PF6] as functional monomers have higher adsorption capacity and better specificity in comparison with those synthesized with traditional acrylamide, and other ionic liquids, such as [AMIM][BF4] and [AMIM]C1, as functional monomers.4. The main acting force that determined the adsorption capacity and selectivity to BSA is the specific adsorption force between the target moleculars and the imprinting sites on MIPs. Hydrogen bonding is dominant in the specific adsorption force.