We herein report aqueous fabrication of well-defined Au@CuE (E = S, Se) core@shell dual plasmonic supraparticles (SPs) for multimodal imaging and tumor therapy at the in vivo level. By means of a modified self-limiting self-assembly based strategy, monodisperse core@shell dual plasmonic SPs, including spherical Au@CuS SPs, Au@CuSe SPs, and rod-like Au@CuS SPs, are reliably and eco-friendly fabricated in aqueous solution. Due to plasmonic coupling from the core and shell materials, the as-prepared hybrid products possess an extremely large extinction coefficient (9.32 L g cm for spherical Au@CuS SPs) at 808 nm, which endows their excellent photothermal effect. Furthermore, the hybrid core@shell SPs possess the properties of good biocompatibility, low nonspecific interactions, and high photothermal stability. So, they show favorable performances for photoacoustic imaging and X-ray computed tomography imaging as well as photothermal therapy of tumors, indicating their application potentials in biological field.

The exploration of magnetic resonance imaging (MRI) agents possessing excellent performances and high biosafety is of great importance for both fundamental science research and biomedical applications. In this study, we present that monodisperse Fe2O3 supraparticles (SPs) can act as T 1-weighted MRI agents, which not only possess a distinct off–on MRI switch in the tumor microenvironment but also are readily excreted from living bodies due to its quasi-amorphous structure and hierarchical topology design. First, the Fe2O3 SPs have a surface-to-volume ratio obviously smaller than that of their building blocks by means of self-assembly processes, which, on the one hand, causes a rather low r 1 relaxivity (0.19 mM–1 s–1) and, on the other hand, can effectively prevent their aggregation after intravenous injection. Second, the Fe2O3 SPs have a dramatic disassembly/degradation-induced active T 1-weighted signal readout (more than 6 times the r 1 value enhancement and about 20 times the r 2/r 1 ratio decrease) in the tumor microenvironment, resulting in a high signal-to-noise ratio for imaging performances. Therefore, they possess excellent in vivo imaging capacity, even with a tumor size as small as 5 mm3. Third, the disassembled/decomposed behaviors of the Fe2O3 SPs facilitate their timely clearance/excretion from living bodies. In particular, they exhibit distinct renal clearance behavior without any kidney damage with the right dosage. Fourth, the favorable biodegradability of the as-prepared Fe2O3 SPs can further relieve the concerns about the unclear biological effects, particularly on nanomaterials, in general.

The design, catalytic process, and property study of nanozymes are of importance for both fundamental research and application demand. Here, the peroxidase‐mimicking properties of a series of carbon dots (C‐dots) was systematically investigated and they were found to be probably closer to their natural counterparts, as compared to the known corresponding nanozymes. Firstly, four kinds of metal‐free and surface‐modulated C‐dots were bottom‐up fabricated using glucose, α‐cyclodextrin (CD), β‐CD, and γ‐CD as precursors, respectively, and their formation processes, structures, as well as surface chemistry were investigated. Secondly, in the peroxidase‐mimicking catalytic system, no hydroxyl radicals were produced, which indicates a different and special catalytic mode. By employing a joint experimental–theoretical study, a probable catalytic mechanism is proposed. Thirdly, the present C‐dots maintained well their catalytic activity even in complicated serum matrices because their catalytic performances are completely irrelevant of any cation‐related binding sites. Finally, the catalytic performances of the as‐prepared C‐dots were modulated by either pre‐engineering NP surface structures or subsequently introducing photo‐regulated host–guest reactions.