High-stabilized polydopamine modified low eutectic fatty acids based on near-infrared response for breast cancer therapy.

Low eutectic of lauric acid and stearic acid is one of drug loading candidates for its phase transformation at a certain temperature. Herein we demonstrated a combined photothermal-chemotherapy for breast cancer with near-infrared (NIR) triggered phase transition materials (PCM), which was conjugated with polydopamine (PDA) as the photosensitive agent. The PCM nanoparticles had diameters of ~75 nm based on scanning electron microscope (SEM) and dynamic laser scattering (DLS) measurement. Systematic in vitro and in vivo studies have been performed to investigate the stability, biosafety, photothermal performance, and drug delivery and release of PCM conjugates. Temperature measurement confirmed the prepared PDA modified material still showed strong photothermal effect after five cycles, which was higher than that of IR780 conjugated ones. In vivo photothermal imaging showed that the temperature of the tumor site reached 50.8 °C after 3 h of intravenous injection of PCM conjugates. More effective therapy of near-infrared (NIR)-assisted PDA-M@PCM in 4T1 bearing mice was witnessed when compared with that of non-NIR-assisted ones. Enhanced therapy in 4T1 tumor was demonstrated in DOX-loaded PDA-M@PCM by fluorescence imaging. This NIR-triggered PCM based nanoplatform can serve as useful tool for light-assisted combined tumor therapy.