Tumor-Targeted Pt-Cu Nanoplatform for Photothermat Therapy Guided by the Second Near Infrared Window Photoacoustic Imaging

A nanoplatform Pt-Cu@PLL@HA based on Pt-Cu nano-alloys encapsulated in the positively charged polylysine (PLL) and negatively charged hyaluronic acid (HA) was constructed via layer-by-layer (LBL) self- assembly technology. HA not only prolonged the blood circulation time of Pt-Cu@PLL@HA, but also realized the active tumor targeting and enhanced its high accumulation in tumor region. After fast HA degradation in response to hyaluronidase (HAase) in the tumor microenvironment, the site-specific exposure of Pt-Cu@PLL(+) was conducive to the uptake of tumor cells. Owing to the strong NIR- II (the second near-infrared window) absorption capability of Pt-Cu alloy, the effective photothermal tumor ablation could be realized by the precise guidance of NIR- II photoacoustic imaging.