Prussian Blue@Polyacrylic Acid/Au Aggregate Janus Nanoparticles for CT Imaging‐guided Chemotherapy and Enhanced Photothermal Therapy

Abstract Janus nanoparticles (JNPs) have been widely researched for numerous biomedical applications. However, few studies have integrated enhanced photothermal therapy, effective chemotherapy, and diagnostic imaging in a single nanoplatform. Here, unique Prussian blue@polyacrylic acid/Au aggregate JNPs (PB@PAA/Au‐A JNPs) are prepared by a facile and mild method. The exposed surfaces in the JNPs maintain and utilize the original photothermal properties of the PB and Au domains. A heterostructure also adds the functionality of drug loading, which cannot be realized in a common core–shell structure. Notably, the coupling effect of two distinct PB and Au‐A domains leads to a superior photothermal conversion efficiency ( η ) of 49.4%, which is 9.9% higher than that of PB NPs. Synthesized doxorubicin‐loaded PB@PAA/Au‐A JNPs (DOX‐loaded PB@PAA/Au‐A JNPs) can be applied to computed tomography imaging‐guided chemotherapy and enhanced photothermal therapy, collectively promoting tumor inhibition.