Chenodeoxycholic Bile Acid Molecular Imprinted Polymer Composite Microspheres Preparation And Performance Study

Molecularly imprinted polymer(MIP) is a functional polymer material with special recognization and combination for target molecules.In molecularly imprinted technique,the polymerized functional monomers via cross-linking formed molecularly imprinted polymer in the presence of a template molecule,after the template molecules were removed from the resultant polymer network,a template-fitted cavity was left in the molecularly imprinted polymer.The combined functional monomers with the template molecules through hydrogen bonding,electrostatic interaction,complexation and so on formed a preorganized supramolecular assembly before polymerization.Consequently,the imprinted polymers exhibit the template-selective binding ability. The molecularly imprinted polymers have been widely used as chromatographic separation materials, solid phase extractors,catalysts,chemosensors and artificial antibodies.Molecularly imprinted polymer microspheres(MIPMS) were obtained by deposition polymerization using methyacrylic acid(MAA) as functional monomer,trimethylolpropane trimethacrylate(TRIM) and ethylene glycoldimethacrlate(EDGMA) as the cross-linkers, Chenodeoxycholic acid(CDCA) as the template molecular and 2,2-Azobisisobutyronitrile(AIBN) as the initiation agent.The average size of the molecularly imprinted polymer microspheres was between 200 nm and 300 nm.The binding characteristic of the template was evaluated by Scatchard analysis.The selective adsorption of the MIPMS to different target molecules was studied.The result indicated that there were two class binding sites in the MIPMS.The MIPMS showed specific affinity toward chenodeoxycholic acid.Porous polyacrylamide microspheres of partly hydrolysis(p-PAMMS) were prepared by a reverse suspension polymerization technique and freeze-drying.The morphologies and composition of p-PAMMS were characterized by scanning electron microscopy(SEM) and IR spectra respectively.The result revealed that p-PAMMS had regular porous structure on the surface,and there were many -COOH and -CONH₂ groups existing on the microspheres.The prepared p-PAMMS can be used as microcarrier for the composite microspheres of the molecular imprinted polymer.The formed composite microspheres(p-PAMMS/MIPMS) of the polyacrylamide microspheres of partly hydrolysis with the molecularly imprinted polymer microspheres were obtained by deposition polymerization using p-PAMMS as microcarrier,chenodeoxycholic acid(CDCA) as the template molecule,methyacrylic acid(MAA) as functional monomer and trimethylolpropane trimethacrylate(TRIM) as the cross-linker.The occured the interaction between template molecule and functional monomer was characterized by UV-vis spectra.The morphologies of p-PAMMS/MIPMS were investigated by scanning electron microscopy(SEM).The selective adsorption behavior of p-PAMMS/MIPMS to different target molecules was studied.The results indicated that p-PAMMS/MIPMS had better specific affinity toward CDCA.