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&mSiO2 was 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 cm3 g-1, and the specific surface area was 489.0 m2 g-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 microwavesensitive release properties along with good bio-compatibility. Fe3O4@TiO2&mSiO2 Janus nanoparticles are expected to be ideal drug carriers. .