The development of functional copper nanoclusters (Cu NCs) is becoming increasingly widespread in consumer technologies due to their applications in cellular imaging and catalysis. Herein, we report a simple protein-directed synthesis of stable, water-soluble and fluorescent Cu NCs, using BSA as the stabilising agent. Meanwhile, in this study, hydrazine hydrate (N₂H₄·2H₂O) was used as the reducing agent. N₂H₄·2H₂O was a mild reducing agent suggesting that all processes could be operated at room temperature. The as-prepared Cu NCs showed red fluorescence with a peaking center at 620 nm (quantum yield 4.1%). The fluorescence of the as-prepared BSA-Cu NCs was responsive to pH in that the intensity of fluorescence increased rapidly by decreasing the pH from 12 to 6. Besides, with an arresting set of features including water-dispersibility, red fluorescence, good biocompatibility, surface-bioactivity and small size, the resultant BSA-Cu NCs could be used as probes for cellular imaging and catalysis. In this study, CAL-27 cells and the reaction of oxidation of styrene are used as models to achieve fluorescence imaging and elucidate the catalytic activity of the as-prepared BSA-Cu NCs.

Although the synthesis of two-dimensional (2D) layered MoS2 nanomaterials have been developing rapidly, there are many technical issues in preparing MoS2 quantum dots (QDs) with photoluminescence property. Herein, we design a facile colloidal chemical route to prepare photoluminescent MoS2 QDs using the ammonium tetrathiomolybdate ((NH4)2MoS4) as precursors and oleyl amine as reducing agent. The optical property and structure of as-prepared MoS2 QDs are investigated systematically. Resultant MoS2 QDs exhibit fluorescence (λmax=575 nm; quantum yield, 4.4%), spherical morphology with uniform thickness of ~3 nm and excitation-dependent PL phenomenon. Moreover, resultant MoS2 QDs show size-dependent tunable photoluminescence in wide visible region. With the help of the amphiphilic compound, resultant MoS2 QDs could be transferred from organic to aqueous phase. MoS2 QDs in aqueous solution have many advantages, such as good dispersion, low toxicity and photoluminescent property which make them possess promising applications in optoelectronic and biological fields. In this study, the 293T cells are used as a model to evaluate the fluorescence imaging of MoS2 QDs. The results confirm fluorescent signal appears in cytoplasm which demonstrates asprepared MoS2 QDs could be used as a probe for real-time optical cellular imaging.

Herein, a facile and one-step hydrothermal route is designed to synthesize fluorescent carbon dots (CDs) with citric acid (CA) as a carbon source and hyperbranched polyethyleneimine (PEI) as a surface passivation agent. The resultant CDs display strong blue fluorescence with a quantum yield up to 24.3 %. The resultant CDs show excellent photoluminescence properties with high photo-and metal-stability, which are attributed to PEI, a surface passivation agent that would form a protecting layer. Due to the water solubility and low toxicity, the as-prepared CDs possess potential applications in biological labelling. Additionally, PEI is a functional polycationic polymer with various amine groups, which makes the CDs exhibit pH-responsive optical properties. The resultant CDs have been used as pH sensors due to the reversible pH-responsive fluorescence from acidic (pH 3) and basic solutions (pH 11). Moreover, the fluorescence intensity increases with increasing concentrations of CDs.

A one-pot sonochemical reaction of Cu(NO3)2 with glutathione (GSH), the latter functioning as a reducing agent and a stabilizing agent, rapidly affords Cu nanoclusters (NCs). The as-prepared GSH-CuNCs possess a small size (∼2.2 ± 0.2 nm), red luminescence with quantum yield (5.3%), and water-dispersibility. Moreover, the fluorescence of the as-prepared GSH-CuNCs is responsive to pH so that the intensity of fluorescence increases rapidly with decreasing pH from 9 to 4. Besides, the GSH-CuNCs would be aggregated by Pb(2+) ions in aqueous solution which results in quenching of the fluorescence. Therefore, such GSH-CuNCs would be excellent candidates as fluorescent probes for the label-free detection of Pb(2+) with the limit of detection at 1.0 nM. Importantly, CAL-27 cells are used as models to achieve potential application as probes for monitoring Pb(2+) in living cells. Thus, these fluorescent CuNCs could work as an alternative to conventional fluorescent probes for biolabeling, sensing and other applications.

Smart hydrogels are designed and synthesized to exhibit sensitive, linear, and reversible photoluminescence (PL) responses to temperature change in the range of 10 to 50°C.The Eu‐doped core/shell nanoparticle hydrogels consist of poly[styrene‐co‐(N‐isopropylacrylamide)] (PS‐co‐PNIPAM)/PNIPAM.

Herein, luminescent and magnetic copper nanoclusters (CuNCs)a re synthesized by ao ne-pot sonochemical route using glutathione (GSH) as ar educing and stabilizing agent.T he resultant CuNCs show red fluorescence and paramagnetic properties at room temperature. In addition, the as-prepared GSH-CuNCs are water-soluble, exhibit low toxicity,a nd have multifunctional surface chemistry due to the GSH protective layer.F olic acid (FA) was covalently anchored to the GSH-CuNCs, and the nanoprobes were used for highly selective, targeted fluorescent imaging (FI) of gastric cancer HeLa cells with laser scanning confocal microscopy.F inally,t he as-prepared GSH-CuNCs could work as T 1 contrasta gents for magnetic resonance imaging (MRI) due to their paramagnetic properties. These findings highlight the fascinating features of luminescent and magnetic CuNCs, which are ap romising platform for bimodal MRI/FI of cancerc ells.[a] Dr.

Robust diamond meshes with excellent superhydrophobic and superoleophilic properties have been fabricated. Superhydrophobicity is observed for water with varying pH from 1 to 14 with good recyclability. Reversible superhydrophobicity and hydrophilicity can be easily controlled. The diamond meshes show highly efficient water-oil separation and water pH droplet transference.

Herein, we report flowerlike MoS 2 /CdS heterostructures prepared by a simple hydrothermal method. The structure and morphology of products are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results indicate that the as-prepared products show a flowerlike nanostructure with size at 800 nm. This flowerlike nanostructure has a large surface area and may provide a better anchoring surface for adsorbing molecules. Very importantly, as-prepared flowerlike MoS 2 /CdS heterostructures exhibit excellent performance in adsorption and a higher photocatalytic activity for degrading methylene blue under the excitation of visible light than pure CdS or pure MoS 2 . These characteristics enable this novel flowerlike heterostructural nanomaterial to perform potential applications in water treatment, degradation of dye pollutants, and environmental cleaning. Fig. 3 XPS spectra of MoS 2 /CdS (Mo : Cd ¼ 5 : 1) heterostructures (a) Cd 3d; (b) Mo 3d and (c) S 2p.This journal is