The surface inert of luminescent gold nanoparticles (AuNPs) toward biomolecules set a challenge to further exploit their bioanalytical applications using the direct luminescence response. Herein, we report a novel approach to induce significant luminescence quenching of the AuNPs upon the interaction with a metal coordination ligand tris(2-carboxyethyl)phosphine (TCEP), providing a strategy for the detection of H2O2 with a limit of detection (LOD) of 14 nM through the reaction between H2O2 and TCEP to protect the luminescence quenching of the AuNPs. Furthermore, this strategy is also extended for sensitive and selective detection of glucose with a LOD of 1.1 μM based on monitoring the production of H2O2 catalyzed from the oxidation of glucose. The highly extendable feature of this strategy can have great potential in the sensitive detection of other biomolecules.

We report a facile one-step strategy to fabricate luminescent gold nanoparticles (AuNPs) assembled in a sponge-like network with a high capacity for Hg(II) absorption. The tetrathiol pentaerythritol tetrakis 3-mercaptopropionate (PTMP) was employed as both reducing agent and surface coating ligand in the synthesis of 2.4 ± 0.4 nm luminescent PTMP–AuNPs. PTMP also acted as a crosslinker in the formation of a sponge-like network of AuNPs due to thiol-bridging between the ultrasmall PMPT-AuNPs, which resulted in insoluble red-emissive macroscopic aggregates with maximum wavelength at 675 nm followed by a synergistic hydrophobic effect of the surface ligands. Dispersion of the macroscopic aggregates was enhanced using a typical surfactant-assisted method under sonication but did not change the morphology of the sponge-like network of PTMP–AuNPs. The as-prepared sponge-like network of AuNPs provided a good reservoir for the capture of heavy metal ions, and showed a saturation capacity of 2.48 g Hg(II) per gram of sorbent due to the synergistic interaction from both the high porosity of the sponge-like structure and the high-affinity metallophilic Hg(II)–Au(I) interactions. In addition, the excellent optical performance of the network along with the specific and strong closed-shell metal interaction led to a sensitive and selective platform for Hg(II) sensing. Therefore, the sponge-like network of PTMP–AuNPs may find potential applications in Hg(II) detection and elimination from drinking water.

Renal-clearable inorganic nanoparticles (NPs) that hold great potential in the future clinic translations are considered as the next generation of nanomedicine. In the past decade, enormous efforts have been dedicated to the development of renal-clearable NPs with fascinating optical properties, selective disease-targeting capabilities and low nanotoxicities. A further understanding of the design of renal-clearable luminescent metal NPs and their metabolic behavior in the body is important to achieve their clinical transition and extend their bioapplications in disease theranostics. In this review, we discuss the recent synthetic strategies of renal-clearable metal NPs in terms of the considerations of size and composition, surface chemistry and emission wavelength. We also summarize the current disease-related applications of these renal-clearable luminescent metal NPs in tumor targeting, kidney disease and antimicrobial investigations after a discussion of their biological behavior including the pharmacokinetics and biodistribution. Finally, we provide perspectives on the current challenges and upcoming chances for renal-clearable luminescent metal NPs.

We here report a facile pH-guided strategy for the fabrication of water-soluble protein/copper nanoclusters (CuNCs) hybrid nanostructures with stable and bright luminescence resulted from aggregation-induced emission. Using l-cysteine as both the reducing and capping agents, the synthesized CuNCs showed a good reversible pH-responsive aggregation and dispersion in the solution. The CuNCs formed insoluble macroscopic aggregates with stable red-colored emission (620 nm) at pH 3.0 but became soluble with weak luminescence at pH <1.5 or pH >4.0. The highly reversible pH-responsive properties of the CuNCs made it feasible to achieve water-soluble protein/CuNCs hybrid nanostructures in the presence of protein without any external forces (e.g., sonication). The weak luminescent CuNCs were first mixed with protein under neutral condition (e.g., pH 7.0), followed by tuning of the pH to acidic conditions (e.g., pH 3.0) to form luminescent protein/CuNCs hybrid nanostructures, the sizes of which were much smaller than those of the protein-free macroscopic CuNC aggregates. This strategy was easily applicable to other dispersing agents (e.g., glucose oxidase), opening a new pathway for the construction of many other smart water-soluble luminescent biomolecule/nanocluster hybrid nanostructures with various applications.Keywords: copper nanocluster; hybrid nanostructure; noncovalent decoration; self-assembly; water-soluble;

We report a facile one-step strategy to fabricate luminescent gold nanoparticles (AuNPs) assembled in a sponge-like network with a high capacity for Hg(II) absorption. The tetrathiol pentaerythritol tetrakis 3-mercaptopropionate (PTMP) was employed as both reducing agent and surface coating ligand in the synthesis of 2.4 ± 0.4 nm luminescent PTMP–AuNPs. PTMP also acted as a crosslinker in the formation of a sponge-like network of AuNPs due to thiol-bridging between the ultrasmall PMPT-AuNPs, which resulted in insoluble red-emissive macroscopic aggregates with maximum wavelength at 675 nm followed by a synergistic hydrophobic effect of the surface ligands. Dispersion of the macroscopic aggregates was enhanced using a typical surfactant-assisted method under sonication but did not change the morphology of the sponge-like network of PTMP–AuNPs. The as-prepared sponge-like network of AuNPs provided a good reservoir for the capture of heavy metal ions, and showed a saturation capacity of 2.48 g Hg(II) per gram of sorbent due to the synergistic interaction from both the high porosity of the sponge-like structure and the high-affinity metallophilic Hg(II)–Au(I) interactions. In addition, the excellent optical performance of the network along with the specific and strong closed-shell metal interaction led to a sensitive and selective platform for Hg(II) sensing. Therefore, the sponge-like network of PTMP–AuNPs may find potential applications in Hg(II) detection and elimination from drinking water.