Research Progress on Nano-Drug Delivery Systems for Photothermal Cancer Therapy.

Cancer remains one of the most formidable challenges in modern medicine. To mitigate the systemic toxicity associated with conventional therapies such as radiotherapy and chemotherapy, photothermal therapy (PTT) has emerged as a highly promising adjuvant modality. The efficacy of PTT hinges on photothermal agents (PTAs), typically nanomaterials that convert light energy into localized hyperthermia to ablate cancer cells. The convergence of nanotechnology and drug delivery has provided a robust platform for PTT, enabling its integration with other therapeutic modalities to enhance efficacy and reduce side effects. This review constructs a three-dimensional analytical framework based on the "carrier-function-application" paradigm, systematically evaluating four major nanocarrier families: lipids, polymers, proteins, and biomimetics. We critically analyze the unique advantages and challenges of each carrier type when delivering various PTAs and further explore multimodal combination therapy strategies. By synthesizing cutting-edge research, we distill key design principles: the core of an efficient photothermal nanosystem lies in overcoming bottlenecks such as poor tumor targeting and heterogeneous tumor microenvironments through intelligent responsive design and biomimetic modification. This framework provides a clear theoretical basis and practical pathway for developing next-generation PTT platforms characterized by high efficiency, safety, and strong clinical translation potential.