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Creators/Authors contains: "Sun, Xiankai"

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  1. We report the successful synthesis of monodispersed Cu2S nanocrystals and the subsequent formation of highly ordered nanocrystal superlattices. The synthesis is performed under ambient air conditions using simple experimental setups, making the process both accessible and scalable. By systematically tuning the reaction temperature and duration, we demonstrate precise control over the nanocrystal size, which is crucial in achieving uniformity and monodispersity. Furthermore, we uncover a previously unidentified nanocrystal growth mechanism that plays a key role in producing highly monodisperse Cu2S nanocrystals. This insight into the growth process enhances our fundamental understanding of nanocrystal formation and could be extended to the synthesis of other semiconductor nanomaterials. The self-assembly of these nanocrystals into superlattices is carefully examined using electron diffraction techniques, revealing the presence of pseudo-crystalline structures. The ordered arrangement of nanocrystals within these superlattices suggests strong interparticle interactions and opens up new possibilities to tailor their collective optical, electronic, and mechanical properties for potential applications in optoelectronics, nanomedicine, and energy storage. 
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    Free, publicly-accessible full text available May 1, 2026
  2. Abstract Many new technologies, such as cancer microenvironment‐induced nanoparticle targeting and multivalent ligand approach for cell surface receptors, are developed for active targeting in cancer therapy. While the principle of each technology is well illustrated, most systems suffer from low targeting specificity and sensitivity. To fill the gap, this work demonstrates a successful attempt to combine both technologies to simultaneously improve cancer cell targeting sensitivity and specificity. Specifically, the main component is a targeting ligand conjugated self‐assembling monomer precursor (SAM‐P), which, at the tumor site, undergoes tumor‐triggered cleavage to release the active form of self‐assembling monomer capable of forming supramolecular nanostructures. Biophysical characterization confirms the chemical and physical transformation of SAM‐P from unimers or oligomers with low ligand valency to supramolecular assemblies with high ligand valency under a tumor‐mimicking reductive microenvironment. The in vitro fluorescence assay shows the importance of supramolecular morphology in mediating ligand–receptor interactions and targeting sensitivity. Enhanced targeting specificity and sensitivity can be achieved via tumor‐triggered supramolecular assembly and induces multivalent ligand presentation toward cell surface receptors, respectively. The results support this combined tumor microenvironment‐induced cell targeting and multivalent ligand display approach, and have great potential for use as cell‐specific molecular imaging and therapeutic agents with high sensitivity and specificity. 
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