Abstract
A near-infrared (NIR) induced decomposable polymer nanocapsule is demonstrated. The nanocapsules are fabricated based on layer-by-layer co-assembly of azobenzene functionalized polymers and up/downconversion nanoparticles (U/DCNPs). When the nanocapsules are exposed to 980nm light, ultraviolet/visible photons emitted by the U/DCNPs can trigger the photoisomerization of azobenzene groups in the framework. The nanocapsules could decompose from large-sized nanocapsule to small U/DCNPs. Owing to their optimized original size (ca. 180nm), the nanocapsules can effectively avoid biological barriers, provide a long blood circulation (ca. 5h, half-life time) and achieve four-fold tumor accumulation. It can fast eliminate from tumor within one hour and release the loaded drugs for chemotherapy after NIR-induced dissociation from initial 180nm capsules to small 20nm U/DCNPs.