Controlled Self-Assembly of Gold Nanoparticles for Photo-Enhanced Cancer Imaging and Treatment.

Gold nanoparticles (AuNPs) show significant potential for application in cancer imaging and treatment due to their excellent biocompatibility, tunable surface modification, and unique localized surface plasmon resonance (LSPR) effect. In recent years, the self-assembly of AuNPs has emerged as a versatile strategy to meet increasing demands for signal amplification, drug delivery, and therapeutic activation by regulating interparticle spacing and spatial configuration. Compared with dispersed AuNPs, self-assembled AuNPs significantly enhance near-infrared absorption, photothermal conversion efficiency, and multimodal imaging performance, while improving tumor retention, deep penetration, and tumor microenvironment (TME)-responsive behaviors. This review systematically reviews current driving forces for the self-assembly of AuNPs, including hydrophobic interaction, host-guest interaction, hydrogen bonding, and electrostatic interaction, and focuses on summarizing the latest progress of self-assembled AuNPs for cancer imaging and treatment. Finally, this review discusses the remaining challenges in this field, including in vivo and in situ assembly regulation, biological safety assessment, and clinical translation, and outlines future research directions.