Bioresponsive drug delivery systems that can modulate drug release profiles according to different tumor microenvironment are highly desired for improving cancer therapy. In this work, a pH-responsive nanocarrier, layered double hydroxide (LDH) nanoplates coated with ultrathin mesoporous silica layer (LDH@MS), was fabricated with total thickness of around 9 nm. The coating of ultrathin porous silica significantly improved the stability of nanoplates. Moreover, the LDH@MS exhibited pH responsive functionality due to the degradation of silica shell and LDH under moderately acidic pH condition. Notably, the curcumin loaded LDH@MS displayed nearly five-fold greater antitumor efficacy against human breast cancer cells in vitro and marked tumor inhibition in vivo compared to free curcumin under the same drug dosage, most likely due to high dispersibility of the nanocarrier, as well as responsive and steady release of drug molecules. This study opens new avenues to design safer and more effective drug delivery systems with improved therapeutic outcomes.
Keywords: LDH; biodegradability; environment stability; pH-responsive tumor therapy; ultrathin mesoporous silica shell coating.