Synthesis and Characterization of Fe3O4@Au@Molecularly Imprinted Polymers (Fe3O4@Au@MIP) for Selective Release and Uptake of Thiopental Barbiturate

Fe3O4@Au nanoparticles (core:Fe3O4, shell:Au) have received considerable attention because of their advantageous properties arisen from both individual Au and Fe3O4 nanoparticles. Specially, the coating of the magnetic Fe3O4nanoparticles to the biocompatible metal, gold, prevents not only the chemical and enzymatic degradation of the Fe3O4core, but also seems to be suitable for further binding of various types of compounds (especially sulfur-containing ones) and functionalization. Molecularly imprinted polymers (MIPs) that provide a surface for recognizing and binding a specific therapeutic substance, has an enormous potential to revolutionize the performance of drug delivery systems. MIPs can provide other advantages, such as tailored predefined drug recognition systems with binding site functionality, allowing for precise control of drug release or up take [1,2]. To benefit advantages of both Fe3O4@Au nanoparticles and MIPs, in this study, we prepare MIP network on Fe3O4@Au nanoparticles (Fe3O4@Au@MIP; core:Fe3O4, middle layer:Au, shell: MIP). Barbiturates, the most common drugs used in the practice anesthesiology, were used as template. In order to synthesize Fe3O4@Au@MIP, firstly Fe3O4@Auwas synthesized by three-step method; Fe3O4 nanoparticles were prepared by co-precipitation and reduced to Fe2O3 by nitric acid, and then Fe2O3 nanoparticles were used as seeds in sodium citrate solution to reduce the HAuCl4,then, Fe3O4@Ausurface was functionalized with thiol compounds. Secondly, MIP was prepared by using of thiopental as a template, methacrylic acid as the functional monomer, ethylene glycol dimethacrylateas the cross-linker and AIBN as initiator. The resulting nanoparticles were characterized using TEM, FTIR, UV–Vis, XRD and their release and rebind behaviors were studied.