Indocyanine Green-Based Theranostic Nanoplatform for NIR Fluorescence Image-Guided Chemo/Photothermal Therapy of Cervical Cancer

PURPOSE: Indocyanine green (ICG) is a favorable fluorescence nanoprobe for its strong NIR-I fluorescence emission and good photothermal capabilities. However, the stability and tumor targeting ability of ICG is poor, which limits its further applications. To further improve the photothermal and therapeutic efficiency of ICG, bovine serum albumin (BSA) was utilized to encapsulate the ICG and the chemotherapeutic drug doxorubicin (DOX) was loaded to form the BSA@ICG-DOX theranostic nanoplatform. METHODS: In this study, ICG-loaded BSA nanoparticles (NPs) and the BSA@ICG-DOX NPs were fabricated using reprecipitation methods. Next, the tumour inhibition ability and biocompatibility of the NPs were evaluated. A subcutaneous xenografted nude mice model was established and imaging guided synergetic therapy was performed with the assistance of BSA@ICG-DOX NPs under 808 nm laser irradiation. RESULTS: The BSA@ICG NPs exhibited strong NIR-I fluorescence emission, excellent photothermal properties, biocompatibility, and tumor targeting ability. To further improve the therapeutic efficiency, the chemotherapeutic drug doxorubicin (DOX) was loaded into the BSA@ICG NPs to form the BSA@ICG-DOX theranostic nanoplatform. The BSA@ICG-DOX NPs were spherical with an average size of ~194.7 nm. The NPs had high encapsulation efficiency (DOX: 19.96% and ICG: 60.57%), and drug loading content (DOX: 0.95% and ICG: 3.03%). Next, excellent NIR-I fluorescence and low toxicity of the BSA@ICG-DOX NPs were verified. Targeted NIR-I fluorescence images were obtained after intravenous injection of the NPs into the subcutaneous cervical tumors of the mice. CONCLUSION: To improve the anti-tumor efficiency of the ICG@BSA NPs, the chemotherapeutic drug DOX was loaded into the BSA@ICG NPs. The NIR excitation/emission and targeted BSA@ICG-DOX NPs enables high-performance diagnosis and chemo/photothermal therapy of subcutaneous cervical tumors, providing a promising approach for further biomedical applications.