- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
In Vivo Chemoselective Photoacoustic Imaging of Copper(II) in Plant and Animal Subjects
摘要： The detection of Cu2+ in living plants and animals is of great importance for environment monitoring and disease diagnosis. Here, a near-infrared (NIR) turn-on photoacoustic (PA) probe (denoted as LET-2) is developed for Cu2+ detection in living subjects, such as soybean sprouts and mice. The absorbance band of LET-2 shifts from 625 to 715 nm after the interaction with Cu2+, thus producing strong PA signal output at 715 nm (PA715) as an indicator. The PA715 value is increased as a function of the concentration of Cu2+ (0 × 10?6–20 × 10?6 m), with a calculated limit of detection of 10.8 × 10?9 m. More importantly, both in vitro and in vivo studies in soybean sprouts and mice indicate that the as-prepared LET-2 PA probe is highly sensitive and selective for Cu2+ detection. These findings provide a solution for in vivo detection of metal ions by using chemoselective PA probes.
关键词： animals,photoacoustic imaging,copper detection,in vivo,plants
更新于2025-09-23 15:22:29
-
Bonded-luminescent foam based on europium complexes as a reversible copper (II) ions sensor in pure water
摘要： Developing novel lanthanide complexes to rapidly and reliably sensing Cu2+ ions in pure water is highly challenging. Here, a series long luminescence lifetime luminescent Eu-complex polyurethane foams (Eu-PUFs) porous material by simple one-step co-polycondensation reaction has been successfully assembled. The photoluminescence (PL) results indicated that the pure red emission from Eu3+ ions is selectively quenched upon addition of Cu2+ ions, and barely any interference by other metal ions in pure water, thus making Eu-PUFs as a potential Cu2+ ions sensing material. The original luminescent intensity of Eu3+ ions located 617nm can be recovered about 84% by washing of ethylenediaminetetraacetic acid (EDTA) there times, indicating the sensing ability of Eu-PUFs is highly reversible. Due to the probe molecules Eu (TTA)3 ? Phen-NH2 was bonded into Eu-PUFs through covalent bond linker, so the Eu-PUFs sensors can be utilized to detection of Cu2+ ions in pure water multiple times (more than 20 times) without much effect on the sensitivity, and the limitation of detection (LOD) for Cu2+ in pure water is as low as 0.28 μM. All above mentioned results revealed these Eu-PUFs are excellent and potential Cu2+ ions sensing material in pure water and will be widely used in analytical and biological application fields.
关键词： copper (II) ions detection,fluorescence quenching,Europium complexes,Bonded-luminescent foam
更新于2025-09-23 15:22:29
-
Synthesis, photophysical properties and DFT studies of the pyridine-imidazole (PyIm) Cu(I) complexes: Impact of the pyridine ring functionalized by different substituents
摘要： A series of the pyridine-imidazole (PyIm) Cu(I) complexes with different substituents (bromide (P1), methyl (P2), and phenyl (P3)) attached on the pyridine ring are synthesized and characterized. All the complexes show the typical metal-to-ligand charge transfer (MLCT) absorption in the visible region. Complex P1 with an electron-withdrawing substituent on the pyridine ring, e.g., a bromine group, shows a red shift of the emission wavelength. Conversely, an electron-donating substituent on the pyridine ring in complex P2, e.g., a methyl group, shifts the emission to longer wavelength. Similarly, complex P3 containing the extended π-conjugation system of the ligand also exhibits a red shift of the emission wavelength. All of the complexes exhibit efficient green-yellow emission in PMMA films at room temperature with emission wavelength of 547–569 nm and quantum yields of 24.8–53.0%. Meanwhile, DFT and TDDFT methods were employed to explain the photophysical properties.
关键词： Pyridine-imidazole,Copper (I) complex,Metal-to-ligand charge transfer,Molar extinction coefficient,Density functional theory
更新于2025-09-23 15:22:29
-
A promising CuOx/WO3 p-n heterojunction thin-film photocathode fabricated by magnetron reactive sputtering
摘要： A CuOx/WO3 thin-film based on p-n heterojunction proposed as a highly performance and stable photocathode. The CuOx/WO3 thin-film was deposited by magnetron reactive sputtering layer by layer, followed with slow rate annealing in O2 ambient. This is an excellent method for high-quality and uniform composite thin-film deposition with large areas at a high growth rate. The optimized CuOx/WO3 thin-film photocathode after slow rate annealing at 500 °C in O2 provides an obviously enhanced photoinduced current density of -3.8 mA cm-2 at a bias potential of -0.5 V (vs. Ag/AgCl), which value is 1.5 times higher than that of bared CuOx thin-film. This highly enhanced photoelectrochemical performance is attributed to p-n heterojunction, which accelerates the photogenerated electrons and holes transfer to n-WO3 and p-CuOx, thereby accelerate the separation of photogenerated carries. In addition, WO3 layer covered on the surface of CuOx thin film can improve the stability of Cu2O in electrolytes.
关键词： p-n heterojunction,Tungsten oxide,Photoelectrochemical,Copper oxide,Magnetron reactive sputtering
更新于2025-09-23 15:22:29
-
Colorimetric detection of copper ions using gold nanorods in aquatic environment
摘要： On the basis of that Cu2+ can accelerate the leaching rate of Au by thiosulfate, a colorimetric, unlabeled and non-aggregating gold nanorod (GNR) probe has been developed for the determination of trace-level Cu2+ in aqueous solutions. Our study demonstrates a high sensitivity and rapid response towards Cu2+ with a detectable range (20–200 nM). E?ect factors such as the ratio of NH3/NH4Cl, the concentration of S2O3 2?, the bath temperature and the heating time were researched to investigate the in?uences on the copper detection process by GNRs sensor. The method studied in this project is highlighted by its high selectivity and high tolerance to interferences, which can be used to detect trace amounts of Cu2+ ions in water samples quickly and sensitively, indicating the potential suitability of copper detection in various applications.
关键词： Gold nanorods,Copper ions,Catalytic leaching,Colorimetric detection
更新于2025-09-23 15:22:29
-
Copper Nanowire Dispersion through an Electrostatic Dispersion Mechanism for High-Performance Flexible Transparent Conducting Films and Optoelectronic Devices
摘要： Highly dispersed copper nanowire (CuNW) is an essential prerequisite for its practical application in various electronic devices. At present, the dispersion of CuNW is almost realized through the steric hindrance effect of polymers. However, the high post-treatment temperature of polymers makes this dispersion mechanism impractical for many actual applications. Here, after investigating the relationships between the electrostatic dispersion force and influence factors, an electrostatic dispersion mechanism is refined by us. Under the guidance of this mechanism, high dispersion of CuNW and a record low post-treatment temperature (80 ℃ ) are realized simultaneously. The high dispersity endows CuNW with good stability (–45.66 mV) in water-based ink, high uniformity (65.7 ± 2.5 Ω sq-1) in the prepared transparent conducting film (TCF) (23 cm × 23 cm) and industrial film-preparation process which are the issues that hinder the widespread application of CuNW-based TCF at present. The low post-treatment temperature makes CuNW possible for applying on any substrate. In addition, the charge modifier, 2-mercaptoethanol, enables CuNW to resist oxidation well. Finally, flexible optoelectronic devices employing the CuNW film as the electrode are fabricated and show efficiencies comparable to those of optoelectronic devices on ITO/glass.
关键词： copper nanowires,flexible optoelectronic devices,electrostatic dispersion mechanism,transparent conducting films,post-treatment temperatures
更新于2025-09-23 15:22:29
-
Coumarin-1,2,3-triazole hybrid derivatives: Green synthesis and DFT calculations
摘要： A series of new 1,2,3-triazole-coumarin hybrid system are synthesized from the click reaction between 3-azido coumarin and different aromatic terminal alkyne derivatives in a green manner. All compounds are characterized by IR, NMR and UV–VIS spectroscopy. The experimental observations are further supported by DFT computational studies to investigate the effect of substituents at para position in these compounds.
关键词： CuAAC,1,2,3-Triazole,DFT calculation,Green synthesis,copper (I) catalyst
更新于2025-09-23 15:22:29
-
Hyperspectral signature analysis using neural network for grade estimation of copper ore
摘要： The ever-increasing demand for the different metal and mineral resources from the earth’s subsurface has brought tremendous pressure on the geochemical laboratory for the growing countries. The success of any mining industry relies on the estimated values of ore grade in the mineral deposit. Hence, rapid assessment of ore grade is critical in daily schedule in mines operations. Commonly the assay value is determined by chemical analysis or X-Ray Fluorescence (XRF), which is one of the constrained by real-time grade estimation, duration of sample preparation and processing. Several researches carried out in exploration and revealed that hyperspectral technique is a promising tool for mineral identification and mapping. The goal of the present study is to determine the effectiveness of narrow band spectroscopy in Cu grade estimation. To achieve this, a multilayer feed-forward neural network model has been developed to establish a functional link between hyperspectral signature derived features with the copper grade. Altogether eight different types of features including absorption depth, band depth center, the area under the absorption curve, full width at half maxima were extracted from continuum removed spectra along with derivative reflectance features, e.g. band depth ratio, 1st and 2nd slopes from the hyperspectral profile. The dimensionality was reduced by applying Principal Component Analysis onto the extracted features. The first seven PCAs are then used as input vector of the ANN model. A five-fold cross-validation exercise is carried out for model performance. The high degree of correlation reveals that the PCA generated feature from hyperspectral data coupled with ANN model could be an alternative approach to predict the copper grade for the copper mine.
关键词： copper grade,ore grade estimation,spectral feature,K-Fold cross validation,principal component analysis,artificial neural network
更新于2025-09-23 15:22:29
-
Selective Transfer of Rotationally Commensurate MoS <sub/>2</sub> from an Epitaxially Grown van der Waals Heterostructure
摘要： Large-scale synthesis of high quality two-dimensional (2D) semiconductors are critical for their incorporation in emerging electronic and optoelectronic technologies. In particular, chemical vapor deposition (CVD) of transition metal dichalcogenides (TMDs) via van der Waals epitaxy on epitaxial graphene (EG) leads to rotationally commensurate TMDs in contrast to randomly aligned TMDs grown on amorphous oxide substrates. However, the interlayer coupling between TMDs and EG hinders the investigation and utilization of the intrinsic electronic properties of the resulting TMDs, thus requiring their isolation from the EG growth substrate. To address this issue, we report here a technique for selectively transferring monolayer molybdenum disulfide (MoS2) from CVD-grown MoS2-EG van der Waals heterojunctions using copper (Cu) adhesion layers. The choice of Cu as the adhesion layer is motivated by density functional theory calculations that predict the preferential binding of monolayer MoS2 to Cu in contrast to graphene. Atomic force microscopy and optical spectroscopy confirm the large-scale transfer of rotationally commensurate MoS2 onto SiO2/Si substrates without cracks, wrinkles, or residues. Furthermore, the transferred MoS2 shows high performance in field-effect transistors with mobilities up to 30 cm2/Vs and on/off ratios up to 106 at room temperature. This transfer technique can likely be generalized to other TMDs and related 2D materials grown on EG, thus offering a broad range of benefits in nanoelectronic, optoelectronic, and photonic applications.
关键词： molybdenum disulfide,van der Waals epitaxy,two-dimensional semiconductors,field-effect transistors,copper adhesion layers,transition metal dichalcogenides,chemical vapor deposition
更新于2025-09-23 15:21:21
-
Tracing Boron with Fluorescence and PET Imaging of Boronated Porphyrin Nanocomplex for Imaging Guided Boron Neutron Capture Therapy
摘要： Boron neutron capture therapy (BNCT) induces high-energy radiation within cancer cells while avoiding damage to normal cells that without uptake of BNCT drugs, which is holding great promise to provide excellent control over locally invasive malignant tumors. However, lack of quantitative imaging technique to determine local boron concentration has been a great challenge for nuclear physicians to apply accurate neutron irradiation during the treatment, which is a key factor that has limited BNCT’s application in clinics. To meet this challenge, this study describes coating boronated porphyrins with a biocompatible Poly(lactide–co-glycolide)–monomethoxy-poly(polyethylene-glycol) (PLGA-mPEG) micelle for selective tumor accumulation and reduced toxicity comparing with previously reported boronated porphyrin drugs. Fluorescence imaging and PET imaging were performed, unveiling the potential imaging properties of this boronated porphyrin nanocomplex (BPN) to locate tumor region and to determine tissue-localized boron concentration which facilitates treatment planning. By studying the pharmacokinetics of BPN with Cu-64 PET imaging, the treatment plan was adjusted from single bolus injection to multiple times of injections of smaller doses. As expected, high tumor uptake of boron (125.17±13.54 ppm) was achieved with an extraordinarily high tumor to normal tissue ratio: tumor to liver, muscle, fat and blood were 3.24±0.22, 61.46±20.26, 31.55±10.30 and 33.85±5.73, respectively. At last, neutron irradiation with BPN showed almost complete tumor suppression, demonstrating that BPN holds a great potential for being an efficient boron delivery agent for imaging-guided BNCT.
关键词： copper-64,boron neutron capture therapy,theranostics,positron emission tomography,micelle
更新于2025-09-23 15:21:21