Preparation Of Aspirin Surface Molecularly Imprinted Polymer And Evaluation Of Its Sustained Release Properties

Molecularly imprinted microspheres,as a kind of functional polymer material,have been widely used in drugs detection,separation,and controlled sustained release,etc.In this paper,firstly,hydrophobic molecularly imprinted polymer microspheres were prepared via distillation polymerization,using aspirin(Asp)as the template,acrylamide(AM)as the functional monomer and ethylene glycol dimethacrylate(EGDMA)as the cross-linking agent,based on silica gel modified with APTS and methacryloyl chloride.The drug release efficiency was characterized.The adsorption experiments indicate that the adsorption of MIPs is good.The TGA shows their thermostability is pretty.And the drug diffusion experiment shows that the MIPs have a good sustained release effect.In order to endow the molecularly imprinted microspheres more functions,core-shell molecularly imprinted microspheres were prepared by reflux precipitation polymerization.Firstly,hydrophobic molecularly imprinted cores were prepared via reflux precipitation polymerization,using Asp as the template,Trimethylolpropane trimethacrylate(TRIM)as the cross-linking agent,and methacrylic acid(MAA)as the functional monomer.Then,the hydrophilic shell,using acrylamide(AM)as the hydrophilic monomer,was grafted successfully utilizing the residual vinyls remained on the imprinted cores by free radical polymerization.And the hydrophily of MIPs was characterized.The grafted hydrophilic shell made microspheres achieve good dispersion in water.Besides,the grafted-hydrophilic shell can improve the adsorption of MIPs.