Size-Tunable Gd2O3@Albumin Nanoparticles Conjugating Chlorin e6 for Magnetic Resonance Imaging-Guided Photo-Induced Therapy

Protein nanoparticles as nanocarriers are of particular interest in the field of cancer therapy.Nevertheless, so far a facile fabrication of theranostic protein nanoparticles have been explored with limited success for cancer imaging and therapy.In this work, we demonstrate the controllable synthesis of size-tunable Gd2O3@albumin conjugating photosensitizer (PS) (GA-NPs) using hollow albumin as the nanoreactor for magnetic resonance imaging (MRI)-guided photo-induced therapy.The growth of Gd2O3 nanocrystals within the hollow nanoreactors is well regulated through reaction time, and a typical PS (e.g.chlorin e6) is further conjugated with the protein corona of the nanoreactor through facile chemical coupling, followed by the formation of theranostic GA-NPs.GA-NPs exhibit good longitudinal relaxivity, ideal photostability, enhanced cellular uptakes, and preferable size-dependent tumor accumulation.Moreover, GA-NPs effectively generate remarkable photothermal effect, intracellular reactive oxygen species from Ce6, and subsequent cytoplasmic drug translocation, thereby leading to severe synergistic photothermal and photodynamic cell damages.Consequently, GA-NPs exhibit an in vivo size-dependent MRI capacity with enhanced imaging contrast for effective tumor localization, and also generate a potent synergistic photodynamic therapy/photothermal therapy efficacy under irradiation owing to their enhanced tumor accumulation and strong photo-induced cytotoxicity.These results suggest that GA-NPs can act as a promising theranostic protein nanoplatform for cancer imaging and photo-induced therapy.