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

Abstract In this paper, a new Janus-structured nano drug delivery carrier Fe 3 O 4 @TiO 2 &mSiO 2 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 (Fe 3 O 4 @TiO 2 ), and the rod was ordered mesoporous silica (mSiO 2 ). 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 cm 3 g −1 , and the specific surface area was 489.0 m 2 g −1 . Anticancer drug doxorubicin could be loaded in the mesoporous of the carriers to form Fe 3 O 4 @TiO 2 &mSiO 2 -DOX. The drug loading capacity was 10.4%. Fe 3 O 4 @TiO 2 &mSiO 2 -DOX exhibited acid-sensitive and microwave-sensitive release properties along with good bio-compatibility. Fe 3 O 4 @TiO 2 &mSiO 2 Janus nanoparticles are expected to be ideal drug carriers.