Multipronged design of theranostic nanovehicles with endogenous and exogenous stimuli-responsiveness for precise cancer therapy.

Near-infrared (NIR) light-induced photothermal agent-based stimuli-responsive materials have attracted great interest from researchers. However, the highly smart release with precise control by NIR light is not yet well established because of the lack or inadequacy of intelligent release systems, such as premature release of drug and/or photothermal agent. Herein, we put forward a novel and convenient strategy to synthesize cyanine dye-functionalized polymeric materials, where cyanine dye was schemed to attach to polymeric materials by copolymerization, endowing the polymeric materials with NIR light-responsive photothermal property and fluorescent nature for real-time imaging of endocytosis and intracellular trafficking of nanovehicles. Meanwhile, the chemotherapy drug DOX was introduced into the cyanine-containing polymeric materials via formation of dynamic covalent hydrazone bond to circumvent the blood circulation barrier. The nanovehicles displayed fine pH/NIR light-controlled drug release and excellent tumor intracellular drug transposition, which were ulteriorly combined with photo-triggered hyperthermia for enhanced antitumor effect. Therefore, this multipronged design of theranostic nanovehicles with endogenous and exogenous stimuli-responsiveness provides a novel strategy to attain highly smart drug delivery for precise cancer therapy.