Gold-iron oxide nanoparticle: A unique multimodal theranostic approach for thrombosis

Thrombosis is a major concern worldwide as thrombosis-related deaths are attributed to one in five deaths globally. Establishing a clot-targeting theranostic particle for diagnosis and treatment of thrombosis related diseases is crucial to provide rapid life-saving intervention. Herein, we developed activated platelet targeted gold-iron oxide nanoparticles (AuIONP) as a robust and powerful probe facilitating triple imaging modalities, including magnetic resonance imaging (MRI), photoacoustic imaging (PAI), and fluorescence imaging (FLI). Additionally, the antibody tagged AuIONP was utilised to facilitate photothermal thrombolysis, stimulated by the exposure to near-infrared (NIR) laser at 808 nm. In vivo observation of the targeted AuIONP showed a significant increase in MRI T2*-weighted contrast and up to 3-fold more prominent photoacoustic signal and fluorescence intensity compared to the non-targeted group. Upon exposure to NIR laser at 1.5 W/cm2, the localised temperature increase at the clot was observed in the targeted AuIONP treated group, facilitating a significantly higher reduction of thrombus area compared to the non-targeted treated group. Our work offers an innovative theranostic probe with excellent triple modality imaging and thrombolysis.