Main content area

Formation of Oligonucleotide-Gated Silica Shell-Coated Fe3O4-Au Core–Shell Nanotrisoctahedra for Magnetically Targeted and Near-Infrared Light-Responsive Theranostic Platform

Li, Wei-Peng, Liao, Pei-Yi, Su, Chia-Hao, Yeh, Chen-Sheng
Journal of the American Chemical Society 2014 v.136 no.28 pp. 10062-10075
drug therapy, drugs, gold, iron oxides, magnetic materials, magnetic resonance imaging, magnetism, nanocarriers, nanogold, nanoparticles, neoplasms, oligonucleotides, porous media, silica
A new multifunctional nanoparticle to perform a near-infrared (NIR)-responsive remote control drug release behavior was designed for applications in the biomedical field. Different from the previous studies in formation of Fe₃O₄-Au core–shell nanoparticles resulting in a spherical morphology, the heterostructure with polyhedral core and shell was presented with the truncated octahedral Fe₃O₄ nanoparticle as the core over a layer of trisoctahedral Au shell. The strategy of Fe₃O₄@polymer@Au was adopted using poly-l-lysine as the mediate layer, followed by the subsequent seeded growth of Au nanoparticles to form a Au trisoctahedral shell. Fe₃O₄@Au trisoctahedra possess high-index facets of {441}. To combine photothermal and chemotherapy in a remote-control manner, the trisoctahedral core–shell Fe₃O₄@Au nanoparticles were further covered with a mesoporous silica shell, yielding Fe₃O₄@Au@mSiO₂. The bondable oligonucleotides (referred as dsDNA) were used as pore blockers of the mesoporous silica shell that allowed the controlled release, resulting in a NIR-responsive DNA-gated Fe₃O₄@Au@mSiO₂ nanocarrier. Taking advantage of the magnetism, remotely triggered drug release was facilitated by magnetic attraction accompanied by the introduction of NIR radiation. DNA-gated Fe₃O₄@Au@mSiO₂ serves as a drug control and release carrier that features functions of magnetic target, MRI diagnosis, and combination therapy through the manipulation of a magnet and a NIR laser. The results verified the significant therapeutic effects on tumors with the assistance of combination therapy consisting of magnetic guidance and remote NIR control.