Monodisperse Au–Fe₂C Janus Nanoparticles: An Attractive Multifunctional Material for Triple-Modal Imaging-Guided Tumor Photothermal Therapy

Imaging-guided photothermal therapy (PTT) by combination of imaging and PTT has been emerging as a promising therapeutic method for precision therapy. However, the development of multicomponent nanoplatforms with stable structures for both PTT and multiple-model imaging remains a great challenge. Herein, we synthesized monodisperse Au–Fe 2 C Janus nanoparticles (JNPs) of 12 nm, which are multifunctional entities for cancer theranostics. Due to the broad absorption in the near-infrared range, Au–Fe 2 C JNPs showed a significant photothermal effect with a 30.2% calculated photothermal transduction efficiency under 808 nm laser irradiation in vitro . Owing to their excellent optical and magnetic properties, Au–Fe 2 C JNPs were demonstrated to be advantageous agents for triple-modal magnetic resonance imaging (MRI)/multispectral photoacoustic tomography (MSOT)/computed tomography (CT) both in vitro and in vivo . We found that Au–Fe 2 C JNPs conjugated with the affibody (Au–Fe 2 C–Z HER2:342 ) have more accumulation and deeper penetration in tumor sites than nontargeting JNPs (Au–Fe 2 C–PEG) in vivo . Meanwhile, our results verified that Au–Fe 2 C–Z HER2:342 JNPs can selectively target tumor cells with low cytotoxicity and ablate tumor tissues effectively in a mouse model. In summary, monodisperse Au–Fe 2 C JNPs, used as a multifunctional nanoplatform, allow the combination of multiple-model imaging techniques and high therapeutic efficacy and have great potential for precision theranostic nanomedicines.