Imprinted microspheres doped with carbon nanotubes as novel electroresponsive drug-delivery systems

Novel molecularly imprinted polymers (MIPs) suitable for the electroresponsive release of diclofenac were synthesized by precipitation polymerization in the presence of carbon nanotubes (CNTs). Both conventional and electroresponsive imprinted polymers were synthesized with methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. Preliminary experiments were performed to fully characterize the conventional MIPs and composite materials in terms of their morphological properties, recognition behavior, and electric resistivity. In vitro release experiments were performed in aqueous media to elucidate the ability of the MIPs and spherical imprinted polymers doped with CNTs to release the loaded template in a sustained manner over time in comparison to the that of the corresponding nonimprinted materials. Furthermore, a 20-V direct-current voltage was applied through the releasing media to evaluate how the electric field influenced the drug release to demonstrate the suitability of the proposed macromolecular system as an electroresponsive drug-delivery device. (C) 2013 Wiley Periodicals, Inc.