Construction of nanoceria-capped mesoporous silica carriers for redox/pH-responsive drug release

Abstract In this work, we prepared three kinds of mesoporous silica (MS) nanoparticles (NPs) with different aspect ratio. These samples are uniform spheres (MS1) with diameter of 100 nm and nanorods (MS2 and MS3) with same diameter, and the corresponding aspect ratio was 1, 2 and 3, respectively. The as-prepared MS samples presented aspect ratio-dependent specific surface area, cell uptake rate and drug loading capacity. The MS3 sample showed higher cell uptake rate and specific surface area (984 m2g-1), which was used as carrier to construct drug delivery system. Doxorubicin (Dox) is used as model drug to evaluate the release performance of MS3 carriers. After loading Dox, ceria (CeO2) NPs were capped on the surface of MS3 carriers to block the loaded-drug. Due to the dissolution of CeO2 in acidic or reducing environment, the MS3/CeO2 system displayed redox/pH-responsive and sustained release behavior.