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In this paper, the luminescent complex Eu(3-thenoyltrifluoroacetonate)3 was integrated with Fe3O4 and gold (Au) nanoparticles to form a multifunctional nanocomposite, Fe3O4/Au/Eu(TTA)3 (FOASET NC), for dual magnetic-photothermal therapy and biomedical imaging. Upon functionalization with amine-NH2, the FOASET NC exhibits a small size of 60–70 nm and strong, sharp emission at λmax = 614 nm, enhanced by surface plasmon resonance (SPR) of Au nanoparticles that provided an effective label for HT29 colorectal cancer cells by fluorescence microscopy imaging. In addition, a hyperthermia temperature (42–46 °C) was completely achieved by using these FOASET NCs in an aqueous solution with three heating modes for (i) Magnetic therapy (MT), (ii) Photothermal therapy (PT), and (iii) Dual magnetic-photothermal therapy (MPT). The heating efficiency was improved in the dual magnetic-photothermal heating mode. [ABSTRACT FROM AUTHOR]

[Display omitted] • BiSbO 4 nanobundles were synthesized by a facile template-free hydrothermal reaction. • BiSbO 4 nanobundles containing twin nanoseeds enclosed by exposed {0 1 0} facets. • The total DDT photodegradation efficiency of the twin BiSbO 4 is greatly enhanced. • Boosted photoactivity is due to both {0 1 0}-exposed facets and twin structure. Twin engineering is one of the most recent perspective photoactivity enhancing approaches with its ability to provide highly ordered atomic arrangements that accelerate both the transport of free charge carriers and the electron-hole separation, but is still limited to a few photocatalysts, however. In this research, we report the controllable template-free synthesis and UV-photocatalytic activity of twin BiSbO 4 nanoseeds with {0 1 0}-exposed facets for dichlorodiphenyltrichloroethane (DDT) degradation extracted from highly and long-term contaminated soils for the first time. The results revealed that the formation of the desirable BiSbO 4 was strongly affected by precursors and hydrothermal time. Astonishingly, at optimized synthesis conditions, the as-synthesized BiSbO 4 nanobundles containing twin nanoseeds enclosed by exposed {0 1 0} facets with an average length of 60 nm and width of 20 nm were resulted purely. The greatly enhanced photodegradation efficiency of the optimized sample with 98.5 ± 0.83 % removal of total DDT after 4 h of UV irradiation was achieved, significantly higher than that of the bulk sample (62.5 ± 0.77 %). The existence of both the exposed high-energy {0 1 0} facets and the coherent twin boundaries was suggested to contribute to the boosting of the DDT photocatalytic activity of the twin BiSbO 4 nanoseeds with {0 1 0}-exposed facets. Additionally, a twin-dependent photocatalytic mechanism was also proposed for the twin BiSbO 4. [ABSTRACT FROM AUTHOR]

The nanostructured particles of europium(III) complexes with tri-n-octyl phosphineoxide (TOPO) and naphthoyl trifluoroacetone (NTA) ligands containing gold nanoparticles (GNPs) were successfully prepared by using the modified Stöber method. Their morphologies and optical properties were investigated. The results show that they are stable in aqueous solution. The TEM image indicates that the average diameter of nanoparticles of europium(III) complexes containing GNPs is about 115 nm. Monosize nanospheres containing GNPs of 18 nm were produced. The nanostructured luminescent complexes of europium(III) integrated with plasmon structure of GNPs exhibit efficient luminescence properties. [ABSTRACT FROM AUTHOR]

We present a visual tool and facile method to detect MCF-7 breast cancer cells by using YVO4:Eu3+@silica-NH-GDA-IgG bio-nanocomplexes. To obtain these complexes, YVO4:Eu3+ nanoparticles with a uniform size of 10–25 nm have been prepared firstly by the hydrothermal process, followed by surface functionalization to be bio-compatible and conjugated with cancer cells. The YVO4:Eu3+@silica-NH-GDA-IgG nanoparticles exhibited an enhanced red emission at 618 nm under an excitation wavelength of 355 nm and were strongly coupled with MCF-7 breast cancer cells via biological conjugation. These bio-nanocomplexes showed a superior sensitiveness for MCF-7 cancer cell labelling with a detection percentage as high as 82%, while no HEK-293A healthy cells were probed under the same conditions of in vitro experiments. In addition, the detection percentage of MCF-7 breast cancer cells increased significantly via the functionalization and conjugation of YVO4:Eu3+ nanoparticles. The experimental results demonstrated that the YVO4:Eu3+@silica-NH-GDA-IgG bio-nanocomplexes can be used as a promising labelling agent for biomedical imaging and diagnostics. [ABSTRACT FROM AUTHOR]

The multifunctional Fe 3 O 4 /Au/Eu [1-(2-Naphthoyl)-3,3,3-trifluoroacetone] 3 nanocomposite (NC) composed of luminescent europium(III) complex with 1-(2-naphthoyl)-3,3,3- trifluoroacetone (NTA) ligands (Eu(NTA) 3), superparamagnetic Fe 3 O 4 and plasmonic gold nanoparticles (FAEu(NTA) 3) is developed for theranostic application. The FAEu(NTA) 3 NC has been functionalized by 3-(mercaptopropyl)trimethoxysilane/3-(triethoxysilyl)-propylamine (MCPMS/TESPA) and conjugated with IgG antibody. This study was focused on luminescent properties and evaluation of the temperature dependent luminescence of FAEu(NTA) 3 NC. The in vitro fluorescent imaging test of the prostate cancer PC3 cells incubated with FAEu(NTA) 3 NC has been also presented. Image 1 •Novel luminescent-magnetic-plasmonic material for nanotheranostics was reported. •Fe3O4/Au/Eu [1-(2-Naphthoyl)-3,3,3-trifluoroacetone]3 nanocomposite was synthesized. •High photostability and enhanced luminescence by Au NPs-induced SPR were achieved. •Photobleaching were avoided. •In-vitro fluorescent imaging of prostate cancer PC3 cells was obviously observed. [ABSTRACT FROM AUTHOR]

Hollow nanosphere H-Gd2O3:Eu3+ was fabricated by multi-step chemical incorporated with hole soft mold using glucose. The H-Gd2O3:Eu3+ monodisperse nanosphere was obtained after thermal treatment at 650 °C. The structural, morphological, and luminescence optical properties of fabricated transparent samples were determined by X-ray diffraction, transmission and field-emission scanning electron microscopies, UV–Visible spectroscopy, Fourier transform infrared spectroscopy, photoluminescence spectroscopy, and Brunauer–Emmett–Teller method. The hollow nanospheres with diameter in the range of 80-100 nm, and the thickness of the shell is about 19 nm tightly packed by nanoparticles. The material is strongly luminescent in the red region, peak emissions correspond to transition characteristics such as 580 (5Do – 7Fo), 592 (5Do – 7F1), 611 (5Do – 7F2), 650 (5Do – 7F3), and 692 nm (5Do – 7F4). The luminescence efficiency was calculated based on the Judd–Ofelt theory, the luminescence efficiency of hollow nanosphere H-Gd2O3:Eu3+ is higher 1.56 than times Gd2O3:Eu3+ 48.45% which leads for many transparent optical devices. [ABSTRACT FROM AUTHOR]

The synthesis, linear optical and nonlinear optical properties, as well as the electrochemical behavior of a series of pro-ligands containing the 4-(4-N,N-dimethylaminostyryl)-1-methyl pyridinium (DASP+) group as a push-pull moiety covalently linked to terpyridine or bipyridine as chelating ligands are reported in this full paper. The corresponding multifunctional RuII and ZnII complexes were prepared and investigated. The structural, electronic, and optical properties of the pro-ligands and the ruthenium complexes were investigated using density functional theory (DFT) and time-dependent (TD) DFT calculations. A fairly good agreement was observed between the experimental and the calculated electronic spectra of the pro-ligands and their corresponding ruthenium complexes. A quenching of luminescence was evidenced in all ruthenium complexes compared with the free pro-ligands but even the terpyridine-functionalized metal complexes exhibited detectable luminescence at room temperature. Second order nonlinear optical (NLO) measurements were performed by Harmonic Light Scattering and the contribution of the DASP+ moieties (and their relative ordering) and the metal-polypyridyl core need to be considered to explain the nonlinear optical properties of the metal complexes. [ABSTRACT FROM AUTHOR]

We report on the synthesis and characterization of folic acid-conjugated silica-modified TbPO4·H2O nanorods for biomedical applications. The uniform shape TbPO4·H2O nanorods with a hexagonal phase were successfully synthesized by wet chemical methods. A novel TbPO4·H2O@silica-NH2 nanocomplex was then formed by functionalizing these nanorods with silica and conjugating with biological agents. The field emission scanning electron microscopy, energy-dispersive X-ray, and X-ray diffraction reveal the morphology and structure of the nanorods, with their controllable sizes (500-800 nm in length and 50-80 nm in diameter). The Fourier transform infrared spectroscopy was employed to identify chemical substances or functional groups of the TbPO4·H2O@silica-NH2 nanocomplex. The photoluminescence spectra show the four emission lines of TbPO4·H2O@silica-NH2 in folic acid at 488, 540, 585, and 621 nm under 355 nm laser excitation, which could be attributed to the 5D4-7 F j (J = 6 , 5 , 4 , 3) transitions of Tb3+. The TbPO4·H2O@silica-NH2 nanorods were conjugated with folic acid for the detection of MCF7 breast cancer cells. The obtained results show a promising possibility for the recognition of living cells that is of crucial importance in biolabeling. [ABSTRACT FROM AUTHOR]

In this report, GdPO4·nH2O and Tb3+-doped GdPO4·nH2O nanorods@silica-NH2 conjugated with IgG antibody were synthesized by applying hydrothermal, sol-gel, and coprecipitation methods successively. The effects of Tb3+/Gd3+ molar ratios of reactants on the size, morphology, and luminescence of the synthesized samples were also investigated. For the optimized GdPO4·nH2O : Tb3+ sample, uniform nanorods sizing from 10 to 30 nm in diameter and from 200 to 300 nm in length were obtained with the strongest luminescence in green color with narrow bands under the UV excitation (325 nm). The results revealed that, after being coated with silica-NH2 and conjugated with IgG antibody, all luminescence characteristic peaks of GdPO4·nH2O : Tb3+ corresponding to the process of energy transfer from Gd3+ to Tb3+ and then the emission from 5D4 → 7FJ (J=6,5,4,3) of Tb3+ were still clearly observed. The initial results of using the optimized Tb3+-doped GdPO4·nH2O nanorods@silica-NH2 conjugated with IgG antibody for rapid selective detection of Naja atra cobra venom were also reported. [ABSTRACT FROM AUTHOR]

In this report, we are presenting the controlled fabrication results of the strong emission YVO 4 : Eu 3+ nanoparticles and nanowires by microwave which is assisted chemical synthesis. The effects of incorporated synthesis conditions such as microwave irradiated powers, pH values and concentration of chemical composition on properties of nanomaterials are also investigated to obtain the controllable size and homogenous morphology. Morphological and optical properties of YVO 4 : Eu 3+ prepared products which have been characterized by X-ray diffraction (XRD), field emission micrcroscopy (FESEM) and photoluminescence spectroscopy. As based from result of synthesized samples, we found that the changing of pH values, microwave irradiated powers and chemical composition rise to change reform the size and shape of materials from nanoparticles (diameter about 20 nm) to wires shape (with about 500÷800 nm length and 10÷20 nm width). The photoluminescence (PL) spectroscopy measurements of YVO 4 : Eu 3+ nanostructure materials under UV excitation showed that: the strong luminescence in red region with narrow lines corresponding to the intra-4f transitions of 5 D 0 – 7 F j ( j =1, 2, 3, and 4) of Eu 3+ ions with the highest luminescence intensity of 5 D 0 → 7 F 2 transition. [ABSTRACT FROM AUTHOR]

Abstract: Coordination polymers (metal–organic frameworks or MOFs) offer the opportunity for fine-tuning the luminescence behavior because of the possibility to entrap in the network pores molecules that can influence the lanthanide (Ln) emission. In this study, Zn (II) and polycarboxylate based MOFs were first pre-formed by solvothermal method, then considered as host-matrix for in situ doping of low-input concentration of Eu3+ and Tb3+ (two most commonly used lanthanides in life science assays), and afterwards lanthanide doped luminescent materials were synthesized. Different characterizations (X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive Spectroscopy (EDS)) were carried out to confirm accordingly MOF's crystallinity, the structure and chemical composition. The study on luminescent properties of the material has revealed an efficient energy transfer from the ligand excited states to the Eu3+ and Tb3+ f-excited states. With quite low input concentrations (8–15%) of doped rare earth ions, these complexes displayed intense emissions at room temperature and proved to be good candidates for red and green emitter luminescent materials. Generally, this design concept can be extended for the preparation of other rare earth coordination polymers. [Copyright &y& Elsevier]

The as-prepared 55-nm BiVO 4 nanocubes possessing surface heterojucntion between coexposed {0 1 0} and {1 1 0} facets were low-temperature prepared with a significant enhanced photoactivity towards methyle orange and diazinon under solar light irradiation. [Display omitted] • {0 1 0}/{1 1 0}-facets coexposed ms -BiVO 4 nanocubes were template-free prepared. • Surface heterojunction between {0 1 0} and {1 1 0} facets was low-temperature formed. • Methyl orange and diazinon photodegradation was remarkly enhanced under solar light. • Charge transfer/separation and photoactivity were boosted via surface heterojunction. We present the low-temperature, template-free synthesis and photocatalytic activity of cubic-shaped monoclinic scheelite BiVO 4 nanocrystals with coexposed {0 1 0}/{1 1 0} facets in this paper. The first-time diazinon photodegradation test over the studied samples under solar light irradiation was also carried out. The results showed that, by selecting suitable preparative parameters, the as-prepared 55-nm BiVO 4 nanocubes with coexposed {0 1 0}/{1 1 0} facets were obtained at hydrothermal temperature as low as 60 °C. The optimized BiVO 4 samples exhibited excellent photocatalytic efficiency for photodegradation of both methyl orange and diazinon under solar light irradiation. This photocatalytic activity enhancement of the {0 1 0}/{1 1 0}-facets coexposed monoclinic scheelite BiVO 4 with respect to that of the bulk counterpart was supposed to be caused by the formation of surface heterojunctions between two adjunct facets of {0 1 0} and {1 1 0} that boost the charge transfer and separation. [ABSTRACT FROM AUTHOR]

The second-order nonlinear optical (NLO) properties of [Ln(hfac)3(diglyme)] (hfac = hexafluo- roacetylacetonate; diglyme = bis(2-methoxyethyl)ether; Ln = La, Ce, Pr, Sm, Eu, Gd, Er, Lu) complexes have been investigated by a combination of electric-field second harmonic generation (EFISH) and harmonic light scattering (HLS) techniques, providing evidence for the relevant role of I electrons in tuning the second- order NLO response dominated by the octupolar contribution. These lanthanide NLO chromophores allow a clean valuation of the influence of f electrons on the quadratic hyperpolarizability and on its dipolar and octupolar contributions. Molecular quadratic hyperpolarizability values measured by the EFISH method, βEFISH, initially increase rapidly with the number of f electrons, the value for the Gd complex being 11 times that of the La complex, whereas this increase is much lower for the last seven f electrons, the βEFISH value of the Lu complex being only 1.2 times that of the Gd complex. The increase of (βHLS), which is dominated by an octupolar contribution, is much lower along the Ln series. Remarkably, the good (βHLS) values of these simple systems, well known for their luminescence properties, are reached at no cost of transparency. [ABSTRACT FROM AUTHOR]

Donor−acceptor−donor tetrazines containing ferrocene moieties and phenyl unit as a -bridge have been synthesized and characterized. UV−vis spectroscopic and cyclic voltamperometric results indicate sizable intramolecular charge transfer interactions in the ground state when the ferrocene is directly bound to the tetrazine. On the other hand, the results show reduction of the electron-donor strength of ferrocene moieties when there is a phenyl linkage. Both tetrazines display a high reduction potential. The role of ferrocenyl groups appear to be detrimental to maximize the cubic hyperpolarizability of tetrazines, as compared to purely organic groups such as thiophene. A possible explanation for this behavior may originate from metal-to-ligand charge transfer processes. [ABSTRACT FROM AUTHOR]