Artificial Nanotargeted Cells with Stable Photothermal Performance for Multimodal Imaging-Guided Tumor-Specific Therapy.

Organic-inorganic hybrid materials have drawn increasing attention as photothermal agents in tumor therapy due to the advantages of green synthesis, high loading efficiency of hydrophobic drugs, facile incorporation of theranostic iron, and excellent photothermal efficiency without inert components or additives. Herein, we proposed a strategy for biomimetic engineering-mediated enhancement of photothermal performance in the tumor microenvironment (TME). This strategy is based on the specific characteristics of organic-inorganic hybrid materials and endows these materials with homologous targeting ability and photothermal stability in the TME. The hybrid materials perform the functions of cancer cells to target homolytic tumors (acting as "artificial nanotargeted cells (ANTC)"). Inspired by the pH-dependent disassembly behaviors of tannic acid (TA) and ferric ion (Fe) and subsequent attenuation of photothermal performance, cancer cell membranes were self-deposited onto the surfaces of protoporphyrin-encapsulated TA and Fe nanoparticles to achieve ANTC with TME-stable photothermal performance and tumor-specific phototherapy. The resulting ANTC can be used as contrast agents for concurrent photoacoustic imaging, magnetic resonance imaging, and photothermal imaging to guide the treatment. Importantly, the high loading efficiency of protoporphyrin enables the initiation of photodynamic therapy to enhance photothermal therapeutic efficiency, providing antitumor function with minimal side effects.