Bi-functional nanocomposite based on phosphor and carbon nanotubes for tumor ablation in a photothermal fiber system with temperature feedback

Photothermal therapy has aroused tremendous attention in the biomedical field as a promising and less-invasive method for tumor ablation, but its development is greatly limited due to lack of efficient and controllable photothermal materials in treatment. Here, a dual-functional composite based on lanthanide-doped nanoparticles and carbon nanotubes has been successfully synthesized for designing the photothermal system. Under near-infrared laser excitation, the composite could effectively convert light energy into thermal energy due to non-radiation relaxation of nanoparticles and carbon nanotubes. More importantly, the optical thermometer was constructed through the luminescence intensity ratio of different upconversion emission bands corresponding to the lanthanide ions in the nanophosphors. Furthermore, we established an optical fiber system with the developed composite for precise tumor treatment. This work verified the feasibility of accurate temperature monitoring and efficient optical heating under near-infrared laser excitation, proposed a design of multifunctional photothermal materials for tumor treatment with the unique advantages of high accuracy and low invasive burden.