Imaging-guided photothermal therapy (PTT) has been emerging as a novel therapeutic method for precision therapy through combination of imaging and PTT together. However, most nanoplatforms both for PTT and multiple-model imaging lack stable structure. So, it is necessary to develop nanomaterial with high stability. Iron carbide nanoparticles (NPs) have been reported by our group as an excellent candidate for imaging-guided PTT with no side effects.
Here, based on the previous results, we incorporated Au into iron carbide to form a truly “multifunctional entities” monodispersed Au-Fe2C Janus nanoparticles (JNPs) with 12 nm for the first time. We further optimized its performance as MR/MSOT/CT imaging agents with high photothermal transduction efficiency relying on its intrinsic properties, which can both provide accurate information for precision diagnosis and ablate tumors for therapy. Due to their brand absorption in the near-infrared range, Au-Fe2C JNPs showed excellent photothermal effect under 808nm laser irradiation with high photothermal transduction efficiency value. We conjugated Au-Fe2C JNPs with affibody ZHER2:342 and found Au-Fe2C-ZHER2:342 JNPs have longer tumor retention times and deeper tumor penetration than Au-Fe2C-PEG JNPs in vivo. Moreover, our results verified Au-Fe2C-ZHER2:342 JNPs can have selectively high therapy efficacy against tumors with low cytotoxicity. All in all, monodispersed Au-Fe2C JNPs can combine multiple-model imaging techniques and high therapeutic efficacy and had great potential for precision theranostic nanomedicines.