Polydopamine-Encapsulated Cyanine Dye Nanoplatform for Near-Infrared Fluorescence Imaging-Guided Photothermal Therapy of Hepatocellular Carcinoma

A multifunctional nanoplatform that integrates near-infrared fluorescence (NIRF) imaging and photothermal therapy (PTT) may provide a revolutionary opportunity for the precise diagnosis and treatment of hepatocellular carcinoma (HCC). In this work, a multifunctional nanoplatform (PDA-IR806 NPs) was fabricated to realize precise localization and effective treatment of HCC. PDA-IR806 NPs were synthesized via the self-polymerization of dopamine (DA) and synergistic coassembly of polydopamine (PDA) with a commercialized near-infrared (NIR) cyanine dye (IR806) in tris-buffer, followed by poly(ethylene glycol) (PEG) surface modification to improve the dispersion stability. The as-prepared PDA-IR806 NPs demonstrated a predominantly worm-like morphology and exhibited excellent photothermal properties. This nanoformulation could be effectively internalized by HepG2 cells. In vitro cellular assays showed that PDA-IR806 NPs had a satisfactory PTT therapeutic effect toward HCC (i.e., HepG2 and Hepa1–6) cells. PDA-IR806 NPs-based PTT could induce cell apoptosis and trigger immunogenic cell death (ICD). In vivo assessments confirmed that PDA-IR806 NPs exhibited good NIRF imaging performance and excellent photothermal antitumor effect for Hepa1–6 HCC tumor-bearing nude mice. Thus, PDA-IR806 NPs could be employed as a promising theranostic nanoplatform for NIRF imaging-guided PTT of HCC.