PH-sensitive molecularly imprinted polymer based on graphene oxide for stimuli actuated controlled release of curcumin

Abstract

A new pH responsive curcumin (CUR) imprinted polymer as drug carrier and selective adsorbent of CUR based on graphene oxide (GO@CUR-MIP) was synthesized via copolymerization of acrylic acid (AA) and acrylated β-cyclodextrin (β-CD) as functional monomers, synthesized cross linker and template of CUR. In this study, a four functionalized cross linker was synthesized using tetraethyl orthosilicate (TEOS) and hydroxyethylmethacrylate (HEMA). Vinyl group modified graphene oxide (GO) was prepared through several step of modification and used as surface of polymerization in order to increase the drug loading capacity of MIP. The products were characterized using Fourier transform infrared spectroscopy (FT-IR), thermo gravimetric analysis (TGA), X-ray powder diffraction (XRD), dynamic light scattering (DLS) and scanning electron microscope (SEM) methods. The batch adsorption experiment showed the high adsorption capacity and selectivity of GO@CUR-MIP nanocomposite toward template even in the presence of other structural analogues. The adsorption mechanism was investigated through adsorption kinetics and adsorption isotherm models. The in-vitro release of CUR from pH responsive GO@CUR-MIP nanocomposite was also evaluated in different pH that confirmed the ability of controlled and sustained release of CUR in response to environmental pH changes as stimulus. The pH responsiveness of the GO@CUR-MIP nanocomposite leaded to well-targeted drug delivery potential of the system while β-CD/CUR inclusion complex improved drug interaction with the nanocomposite. The overall results demonstrated the potential of this novel synthesized system in separation and drug delivery process.