Magnetic targeting and pH-microwave dual responsive Janus mesoporous silica nanoparticles for drug encapsulation and delivery

In this paper, a new Janus-structured nano drug delivery carrier Fe₃O₄@TiO₂&mSiO₂was designed and synthesized, which consisted of a spherical head and a closely connected rod. The head was a nanocomposite of core/shell structure with magnetic spinel ferric tetraoxide core and anatase titanium dioxide shell (Fe₃O₄@TiO₂), and the rod was ordered mesoporous silica (mSiO₂). The nanocarriers showed excellent magnetic targeting capability (saturation magnetization, 25.18 emu g^-1). The core/shell heads endowed the carriers with fine microwave responsiveness. The pore volume of mesoporous nanocarriers was 0.101 cm³g^-1, and the specific surface area was 489.0 m²g^-1. Anticancer drug doxorubicin could be loaded in the mesoporous of the carriers to form Fe₃O₄@TiO₂&mSiO₂-DOX. The drug loading capacity was 10.4%. Fe₃O₄@TiO₂&mSiO₂-DOX exhibited acid-sensitive and microwave-sensitive release properties along with good bio-compatibility. Fe₃O₄@TiO₂&mSiO₂Janus nanoparticles are expected to be ideal drug carriers.