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Marbofloxacin (MB) is a newly developed fluoroquinolone antibiotic used especially as a veterinary drug. It may be regarded as the improved version of enrofloxacin owing to its antibacterial activity, enhanced bioavailability, and pharmacokinetic–pharmacodynamic (PK–PD) properties. In this study, nine heavy rare-earth ions (Y, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) were selected in light of their potential antibacterial activity and satisfactory biosafety to afford the corresponding rare-earth metal complexes of MB: the MB–Ln series. Their chemical structures and coordination patterns were characterized using IR spectroscopy, HRMS, TGA, and X-ray single-crystal diffraction analysis. Our results confirmed that all the MB–Ln complexes yielded the coincident coordination modes with four MB ligands coordinating to the Ln(III) center. In vitro antibacterial screening on five typical bacteria strains revealed that the MB–Ln complexes exhibited antibacterial activities comparable with MB, as indicated by the MIC/MBC values, in which Escherichia coli and Salmonella typhi were the most sensitive ones to MB–Ln. Furthermore, the MB–Ln complexes were found to be much less toxic in vivo than MB, as suggested by the evaluated LD50 (50% lethal dose) values. All the MB–Ln series complexes fell in the LD50 range of 5000–15 000 mg kg−1, while the LD50 value of MB was only 1294 mg kg−1. Furthermore, MB–Lu, as the selected representative of MB–Ln, could effectively inhibit the activity of DNA gyrase, the same as MB, suggesting the primary antibacterial mechanism of the MB–Ln series. The results demonstrated the good prospects and potential of metal-based veterinary drugs with better drug performance. [ABSTRACT FROM AUTHOR]

Improving the fast-charging capabilities and energy storage capacity of electric vehicles presents a feasible strategy for mitigating the prevalent concern of range anxiety in the market. Nanostructure electrode materials play a crucial role in this process. However, the current method of preparation is arduous and yields restricted quantities. In view of this, we have devised an innovative approach that provides convenience and efficacy, facilitating the large-scale synthesis of CoS2 nanoparticles, which exhibited exceptional performance. When the current density was 1000 mA g−1, the discharging capacity reached 760 mAh g−1 after 400 cycles. Remarkably, even at an increased current density of 5000 mA g−1, the discharging capacity of CoS2 remained at 685.5 mAh g−1. The ultra-high performance could be attributed to the specific surface area, which minimized the diffusion distance of sodium-ions during the charging and discharging processes and mitigated the extent of structural damage. Our straightforward preparation techniques facilitate the mass production and present a novel approach for the development of cost-effective and high-performing anode materials for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

The aggravating extreme climate changes and environmental pollution problems have stimulated the exploration of green alternatives to conventional fossil fuels and green environmental treatments. Photocatalysis is recognized as an outstanding green tool for solving the energy crisis and environmental rehabilitation issues. Restricted by the high cost of precious metals, researchers expect to obtain low-cost, efficient and stable photocatalysts. Herein, CdS materials were derived through MOFs and subsequently combined with CoO to form CdS/CoO heterojunctions. The catalytic ability was evaluated by the photocatalytic degradation of tetracycline hydrochloride (TC) and the photocatalytic production of hydrogen. With the integration of CoO, in terms of TC degradation, CdS/CoO heterojunctions can degrade over 90% of TC within 1 hour. In terms of hydrogen production, compared to CdS alone, the hydrogen production efficiency of the CdS/CoO heterojunction increased by 1.7 times. The initial analysis of the reasons for the enhancement of photocatalytic efficiency was conducted by TEM, XPS and other characterization means. Density functional theory (DFT) calculations verified the existence of a built-in electric field in the CdS/CoO heterojunction, which was the essential reason for the improved catalytic performance, and finally, the presence of ˙O2− and ˙OH in the photocatalytic system was demonstrated by the ESR technique. Based on the carrier separation/transfer pathway in the heterojunction, a simple and novel S-type heterojunction scheme was proposed. [ABSTRACT FROM AUTHOR]

It has been recognized that both the ligand fields and intermolecular interactions may greatly impact the electron-transfer-coupled spin transition (ETCST) events in switchable magnetic materials; however, the engineering of these factors within a given system is still challenging. In this article, we chose the 4,4′-substituent 2,2′-bipyridine derivatives as chelating ligands according to their increasing electron-donating strength and incremental potential for forming hydrogen bonds (bpyCHO,CH3(L1) < bpyCH2OH,CH3 (L2) < bpyCH2OH,CH2OH (L3)), and prepared three new [Fe2Co2] complexes, {[(Tp*)Fe(CN)3Co(L)2]2[ClO4]2}·Sol (1, L = L1, Sol = 4MeCN·2H2O; 2, L = L2, Sol = 3MeCN; 3, L = L3, Sol = 4MeOH; Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate). X-ray crystallography studies revealed that all the complexes share similar cyanide-bridged [Fe2Co2] square compositions except for the different substituted groups of L ligands, which led to the clearly evidenced intercluster hydrogen bonds between the neighbouring hydroxyl groups in 2 and 3. As a result, 1 remained in the paramagnetic [Fe III,LS2 Co II,HS2 ] state over the whole temperature range, while 2 and 3 showed complete ETCST behaviour with the transition temperatures (T1/2) being 221 and 294 K, respectively. [ABSTRACT FROM AUTHOR]

Heteroatom doping plays a crucial role in improving the electrocatalytic performance of catalysts towards water splitting. Owing to the existence of Ru–O moieties, Ru is thus emerging as an ideal dopant for promoting the electrocatalytic performance for water splitting by modifying the electronic structure, introducing extra active sites, improving electronic conductivity, and inducing a strong synergistic effect. Benefitting from these advantages, Ru-doped nanomaterials have been widely investigated and employed as advanced electrocatalysts for water splitting, and many excellent Ru-doped electrocatalysts have been successfully developed. In an effort to obtain a better understanding of the influence of Ru doping on the electrocatalytic water splitting performance of nanocatalysts, we herein summarize the recent progress of Ru-doped electrocatalysts by focusing on the synthesis strategies and advantageous merits. Applications of these new materials in water electrolysis technology are also discussed with emphasis on future directions in this active field of research. [ABSTRACT FROM AUTHOR]

Visible-light-promoted [2 + 2] cycloaddition provides a straightforward and efficient way to produce cyclobutanes, which are the core skeleton in commercial pharmaceuticals and fine chemicals. However, the control of the conformation to produce syn-head-to-head (syn-HH) cyclobutanes remains a grand challenge. In this work, we report the design and synthesis of anthraquinone-based metal–organic cages (MOCs) for the [2 + 2] photocycloaddition of chalcones to generate syn-HH cyclobutanes. Guided by the coordination-driven self-assembly strategy, one D2 and three D4h symmetric MOCs are constructed from anthraquinone-derived dicarboxylate linkers and 4-tert-butylsulfonylcalixarene capped tetrametallic clusters. The porous cages feature large hydrophobic cavities and photoactive anthraquinone units and are demonstrated to be efficient and recyclable photocatalysts for [2 + 2] cycloaddition of chalcones. The syn-HH diastereomers are obtained with up to 13 : 1 diastereomeric ratio (dr). The cage catalysts provide a well-defined confined space to accommodate the substrates, thus leading to enhanced selectivity relative to the free anthraquinone catalyst. [ABSTRACT FROM AUTHOR]

The hydrogenation of nitrobenzene to aniline is an important process in the industry of fine chemicals, but developing inexpensive catalysts with expected activity and selectivity still remains a challenge. By using density functional theory calculations, we demonstrated that the isolated Fe atom not only can weaken the adsorption of reactants and reaction intermediates as compared to Fe nanoparticles, but also remarkably decrease the reaction barrier for the hydrogenation of nitrobenzene to aniline. Thus, the Fe single-atom (Fe SA) catalyst is considered as an ideal catalyst for this reaction. This theoretical prediction has been subsequently confirmed by experimental results obtained for the Fe SAs loaded on N-doped hollow carbon spheres (Fe SAs/NHCSs) which achieved a conversion of 99% with a selectivity of 99% for the hydrogenation of nitrobenzene. The results significantly outperformed the Fe nanoparticles for this reaction. This work provides theoretical insight for the rational design of new catalytic systems with excellent catalytic properties. [ABSTRACT FROM AUTHOR]

A new red-emitting phosphor based on polyfluoride Na3Li3Sc2F12 doped with Mn4+ was prepared via a co-precipitation method at room temperature. Its crystal structure, luminescence properties and applications are discussed in detail. The as-synthesized phosphor emits red light with intense zero-phonon line (ZPL) at 618 nm under the excitation of 461 nm light. A higher energy of the 2Eg level of Mn4+ was observed in Na3Li3Sc2F12:Mn4+. The Racah parameters B and C were calculated to be 604 cm−1 and 3840 cm−1, respectively. The as-obtained Na3Li3Sc2F12:Mn4+ (4.86 mol%) shows a high internal quantum efficiency (IQE) of 66.8% and better resistance to thermal quenching. A white light-emitting diode (w-LED) with a high color rendering index of 92 and a low color temperature of 3694 K was fabricated. Hence, Na3Li3Sc2F12:Mn4+ as a new red-emitting phosphor has great potential application in w-LEDs. [ABSTRACT FROM AUTHOR]

Four open-framework Ag–Sn–S compounds K2Ag2Sn2S6 (1); K2Ag2SnS4 (2); Rb2Ag2SnS4 (3); and Cs2Ag2SnS4 (4) have been synthesized using a solvothermal method. Compound 1 possesses a unique three-dimensional (3D) structure in which Ag+ ions are two-coordinated. Compounds 2–4 have the same layered structure in which Ag+ ions are tetrahedrally coordinated. Photocatalytic degradation properties of methylene blue have been investigated and compound 1 displays excellent photodegradation activities. The photoelectric response properties, optical properties, and theoretical calculations of these compounds have also been studied. [ABSTRACT FROM AUTHOR]

A new red-emitting phosphor based on polyfluoride Na3Li3Sc2F12 doped with Mn4+ was prepared via a co-precipitation method at room temperature. Its crystal structure, luminescence properties and applications are discussed in detail. The as-synthesized phosphor emits red light with intense zero-phonon line (ZPL) at 618 nm under the excitation of 461 nm light. A higher energy of the 2Eg level of Mn4+ was observed in Na3Li3Sc2F12:Mn4+. The Racah parameters B and C were calculated to be 604 cm−1 and 3840 cm−1, respectively. The as-obtained Na3Li3Sc2F12:Mn4+ (4.86 mol%) shows a high internal quantum efficiency (IQE) of 66.8% and better resistance to thermal quenching. A white light-emitting diode (w-LED) with a high color rendering index of 92 and a low color temperature of 3694 K was fabricated. Hence, Na3Li3Sc2F12:Mn4+ as a new red-emitting phosphor has great potential application in w-LEDs. [ABSTRACT FROM AUTHOR]

The development of ultrathin two-dimensional metal–organic framework nanosheets (2D MONs) has recently attracted increasing interest due to their extensive application potential originating from their ultrathin thickness, large surface area, and innumerable accessible surface-active sites. In this frontier article, we highlight the recent developments of 2D MONs for highly efficient heterogeneous catalysts; they can be grouped into three sections in terms of their functions: (i) as catalysts capable of showing outstanding intrinsic reactivity, (ii) as support materials for prevalent catalysts, and (iii) as catalysts with multifunctional catalytic activity for diverse organic transformations. In addition, the present challenges and future opportunities in this field are also discussed. [ABSTRACT FROM AUTHOR]

Optimizing structure and varying doped ions are two main strategies to obtain excellent luminescence performance. Spherical morphology is considered to be the most ideal phosphor structure due to the least surface defects. Herein, a series of spherical and monodispersed Dy3+/Eu3+ co-activated SiO2@Gd2O3 core–shell phosphors with multicolor tunable luminescence were successfully prepared via a facile urea assisted precipitation method. Related chemical reactions and the possible growth mechanism of Gd2O3:Ln3+ directional deposition on the surface of SiO2 microspheres were put forward. Upon 273 nm UV radiation excitation, SiO2@Gd2O3:Dy3+ and SiO2@Gd2O3:Eu3+ samples exhibited characteristic yellow (4F9/2–6H13/2) and blue (4F9/2–6H15/2) emissions of Dy3+ and red (5D0–7F2) emission of Eu3+, respectively. Meanwhile, multicolor emissions (warm white, yellow and orange) could be easily obtained by modulating the relative content of Dy3+ and Eu3+ in SiO2@Gd2O3:Ln3+ samples under a single excitation wavelength. Moreover, it was confirmed that Dy3+ could transfer energy to Eu3+ in the form of quadrupole–quadrupole interaction and further improved the luminescence intensity of Eu3+ by comparing experimental data with theoretical calculations. These results imply that tunable luminescence Dy3+,Eu3+ co-doped SiO2@Gd2O3 microspheres have great potential applications in multicolor displays and biolabeling fields. [ABSTRACT FROM AUTHOR]

Defects within the nanoscale UiO-66 metal–organic framework (MOF) are created to lock a hybrid phosphonoacetate ligand through Zr–O–P linkages, leaving the carboxyl group free to anchor cisplatin prodrug cis, cis, trans-[Pt(NH3)2Cl2(OH)2]. A drug loading of 256.5 mg g−1 (25.7 wt% based on cisplatin) was achieved with a Zr6 : Pt : P ratio of 1.5 : 1 : 1, which surpasses defect-free UiO-66 and several other MOF carriers. This framework exhibited a burst release of its payload in PBS solution in the first 2 h, releasing 71% of the drug, including a 50% payload release in less than 1 h. This work demonstrates that MOF defects can be intentionally engineered to achieve a high drug loading, and serves as an alternative to drug encapsulation using the pore void and through the association of the functionalized ligand. [ABSTRACT FROM AUTHOR]

Active removal of recalcitrant antibiotic contaminants for wastewater purification and hydrogen evolution from water splitting using hollow-structured photocatalysts has attracted considerable interest in the field of environmental governance and energy conversion. Herein, 0D Ta3N5 nanoparticles anchored on 3D TiO2 hollow nanosphere composites (0D/3D Ta/Ti) were designed and fabricated via a feasible surface self-assembly process for the first time. Various techniques were employed to characterize the structure and optical properties of the as-prepared samples. The photocatalytic activities of Ta3N5/TiO2 hybrids were systematically evaluated via both photodegradation of levofloxacin (LEV) and water splitting for hydrogen evolution under solar light irradiation. The degradation results showed that the x-Ta/Ti composites exhibit remarkably better performances for LEV degradation than pristine TiO2. The 3 wt% Ta3N5 nanoparticle-loaded hollow TiO2 composite material exhibited optimal photocatalytic activity (92.79%), and its degradation rate constant was 3.04 times that of TiO2. Simultaneously, the 3-Ta/Ti composite also possessed high ability to degrade other antibiotics such as ciprofloxacin (CIP) and tetracycline hydrochloride (TCH) and colored organic dyes such as Rhodamine B (RhB). Besides, x-Ta/Ti composites exhibited higher photocatalytic hydrogen evolution activities compared with TiO2 hollow spheres. The efficient charge transfer and separation between the close heterogeneous interfaces, broadened spectral response range and improved specific surface area were mainly responsible for the superior photocatalytic performance of the x-Ta/Ti nanocomposite. Our study provides an effective strategy for the design of hollow structure composite photocatalysts with excellent photocatalytic performances not only for pollutant removal, but also for efficient solar-to-fuel conversion. [ABSTRACT FROM AUTHOR]

Five stable clusters sharing the cuboidal [Ni4O4] skeleton are subjected to third-order nonlinear optical (NLO) property measurements. Preliminary results suggest that the NLO property is largely defined by the cluster core skeleton and the directly coordinated atoms, with limited contribution from the heavy atoms peripherally attached to the aromatic ligands. [ABSTRACT FROM AUTHOR]

In this work, 3D CdIn2S4 nano-octahedron/2D ZnO nanosheet heterojunctions (CIS/ZO-x) were fabricated for the first time via a facile and green impregnation–hydrothermal method, where three-dimensional (3D) CdIn2S4 nano-octahedra densely anchor onto both sides of 2D ZnO nanosheets to form an embedded nanostructure with intimate interfacial contacts. Various characterization techniques were adopted to measure the morphologies, structures and optical properties of the as-prepared CIS/ZO-x heterojunctions in detail. The photocatalytic performance of the as-prepared CIS/ZO-x was evaluated via the photodegradation of tetracycline hydrochloride (TCH) under visible light irradiation, and the result shows that the hybridization of ZnO nanosheets with CdIn2S4 nano-octahedra significantly enhances the photocatalytic activity of heterojunctions. The highly stable and reusable sample CIS/ZO-2 possesses the highest photocatalytic activity (94.04%), and its rate constant (k = 0.06357 min−1) is about 4.96 and 22.31 times as high as those of pure CdIn2S4 and ZnO. Interestingly, the removal efficiency of TCH and the rate constant are also much higher than those of numerous previously reported composite photocatalysts. The synergistic effect and the unique 3D/2D hybrid structure with intimate interfacial contacts are primarily responsible for the enhanced photocatalytic activity. A possible photocatalytic mechanism for the TCH photodegradation over the CIS/ZO sample is also proposed. This work provides a novel 3D/2D composite photocatalyst for the efficient removal of antibiotic pollutants and will be helpful for designing other 3D/2D heterojunctions. [ABSTRACT FROM AUTHOR]

A new series of lanthanide coordination polymers formulated as [Ln(μ-L)(μ3-L)(H2O)]nXn (Ln/X = Er/Cl (1), Er/Br (2), Tm/Cl (3), Tm/Br (4), Yb/Cl (5), and Yb/Br (6); L = 1,3-bis(4-carboxyphenyl) imidazolium carboxylate(1+)) were solvothermally generated and fully characterized. Single-crystal X-ray diffraction analysis shows that all products possess isomorphous structures that are composed of cationic 1D double chains with encapsulated halide anions. From a topological perspective, such 1D chains can be classified as a binodal 3,5-connected net with a unique topology defined by the point symbol of (3·42)(32·42·53·62·7). All products 1–6 feature a remarkable thermal stability and were applied as highly active heterogeneous catalysts for the coupling reactions between halogenated propylene oxides and CO2 to give the corresponding cyclic carbonates. The reaction conditions, substrate and catalyst scope, and mechanistic features of this catalytic transformation were investigated. High products yields (up to 98%), elevated TONs (up to 3920) or TOFs (up to 326 h−1) were attained under mild reaction conditions. In addition, catalyst 6 can be recycled at least eight times with no loss of catalytic activity. [ABSTRACT FROM AUTHOR]

A dinuclear Ru(ii) complex of [(bpy)2Ru(H2ipaip)Ru(bpy)2]Cl4 {bpy = 2,2′-bipyridine, H2ipaip = 2-(9-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)anthracen-10-yl)-1H-imidazo[4,5-f][1,10]phenanthroline} is newly synthesized and characterized. Singlet oxygen sensing and ground- and excited-state acid–base properties of this complex are studied. The results indicated that the complex acted as a highly sensitive and selective luminescent probe for singlet oxygen (1O2) in neutral and alkaline aqueous media under visible light excitation at 458 nm, resulting in 5.2- and 7.6-fold emission enhancement, respectively. This probe has advantages of visible light excitation, low singlet oxygen detection limits of 2.7–3.1 nM and high water solubility, thus holding great potential for applications in biological systems. [ABSTRACT FROM AUTHOR]

A series of apatite solid solution phosphors Ca2+xLa8−x(SiO4)6−x(PO4)xO2:Eu2+ (x = 0,2,4,6) were synthesized by a conventional high-temperature solid-state reaction. The phase purity was examined using XRD, XPS and XRF. The crystal structure information, such as the concentration, cell parameters and occupation rate, was analyzed using a Rietveld refinement, demonstrating that the Eu2+ activated the Ca2La8(SiO4)6O2 and Ca8La2(PO4)6O2 to form continuous solid solution phosphors. Different behaviors of luminescence evolution in response to structural variation were verified among the series of phosphors. Two kinds of Eu2+ ion sites were proved using low temperature PL spectra (8k) and room temperature decay curves. The substitution of large La3+ ions by small Ca2+ ions induced a decreased crystal field splitting of the Eu2+ ions, which caused an increase in emission energy from the 5d excited state to the 4f ground state and a resultant blue-shift from 508 nm to 460 nm. Therefore, with the crystal structure evolution, the emitted color of the series of phosphors could be tuned from green to blue by adjusting the ratio of Ca/La. [ABSTRACT FROM AUTHOR]

Upon solvothermal reactions between Cd(ii) salt and 5-pyridyl-tetrazolate (4-Ptz) under different reaction conditions, three new Cd(ii) metal–organic frameworks (MOFs), namely [Cd3(4-Ptz)5(H2O)2(μ3-OH)·3DMA·5H2O·CH3OH]n (1), [Cd5(4-Ptz)8(CH3OH)2(μ3-OH)2·2DMA·4H2O·3CH3OH]n (2) and [{Cd9(4-Ptz)14(AC)2(μ3-OH)2(H2O)4}·8DMA·H2O·3CH3OH]n (3), were synthesized based on different highly connected secondary building units (SBUs). In the presence of triethylamine, 1 was constructed based on an 8-connected triangular trinuclear Cd3 SBU and exhibits a three-dimensional framework, while 2 was generated upon the addition of HCl, assembled through a close packing of the octahedron cages consisting of unprecedented 12-connected 4-Ptz bridged Cd5 SBUs and thus showing high thermal and chemical stability. For generating 3, two different kinds of Cd3 SBUs, including an 8-connected triangular SBU and a 10-connected linear SBU, were constructed and further integrated into a distorted octahedron-based net under the addition of both triethylamine and NaCl. In addition to the structural analysis, we also focused on the investigation of gas adsorption and solid-state fluorescence properties of 2. [ABSTRACT FROM AUTHOR]

Two chiral porous Ti(salan)-based metal–organic frameworks are constructed and are shown to be efficient and recyclable heterogeneous catalysts for asymmetric cyanation reaction of aldehydes, displaying significantly higher enantioselectivity than their homogeneous counterpart. [ABSTRACT FROM AUTHOR]

Complexes of yttrium(iii) and dysprosium(iii) with the traditional Chinese medicine active ingredient oxoglaucine (OG), namely [Y(OG)2(NO3)3]·CH3OH (1) and [Dy(OG)2(NO3)3]·H2O (2), were synthesized and characterized by elemental analysis, IR, ESI-MS, 1H and 13C NMR as well as single-crystal X-ray diffraction analysis. In vitro the complexes exhibited higher anticancer activity than the free ligand OG against the tested cancer cell lines. Among the tested cell lines, HepG2 is the most sensitive to the complexes. Complex 2 can trigger DNA damage in HepG2 cells, resulting in cell cycle arrest in the S phase and leading to cell apoptosis. The S phase cell-cycle arrest is caused via the ATM (ataxia-telangiectasia mutated)-Chk2-Cdc25A pathway. Chk2 is phosphorylated and activated in an ATM-dependent manner. It, in turn, phosphorylates Cdc25A phosphatise on serine124, causing the inactivation of Cdc25A in ubiquitin-mediated proteolytic degradation. The cyclin-Cdk complexes of the S phase could also be inhibited by limited supply of cyclins A and E. This irreversible cell cycle arrest process ultimately induces mitochondria-involved apoptotic cell death via the activation of Bcl-2 protein. Complex 2 effectively inhibited tumour growth in the BEL-7402 xenograft mouse model and exhibited higher safety in vivo than cisplatin. [ABSTRACT FROM AUTHOR]

A series of novel binuclear phenoxyimino organoaluminum complexes of the type [(RN=CH)C6H3OAlMe2]2 [R = C6H5 (2a), 2,6-iPr2C6H3 (2b), 2,6-Ph2C6H3 (2c), adamantyl (2d), tBu (2e)] have been prepared in high yields, and these complexes were identified by 1H, 13C NMR and elemental analysis. Structural analysis for 2a–e revealed that these complexes have a distorted tetrahedral geometry around Al and both the Al–O and the Al–N bond distances were considerably influenced by substituents in the imino groups. The complexes were tested as catalyst precursors for ring-opening polymerisation (ROP) of ε-caprolactone (CL) in the presence of BnOH, and their catalytic activities were strongly affected by the catalyst structures and polymerisation conditions. An efficient living ROP has been achieved using the 2b/BnOH system. [ABSTRACT FROM AUTHOR]

Three new lanthanide complexes with dihalo-substituted 8-quinolinol: [Gd(BrQ)3(H2O)2]·1.33EtOH·0.33H2O (1), [Dy(ClQ)3(H2O)2]·1.33EtOH·0.33H2O (2), [Er(ClQ)3(H2O)2]·1.33EtOH·0.33H2O (3) (H-BrQ = 5,7-dibromo-8-quinolinol, H-ClQ = 5,7-dichloro-8-quinolinol) have been synthesized and characterized by elemental analysis, IR, ESI-MS, single-crystal X-ray diffraction and TGA. The single-crystal X-ray diffraction analyses reveal that complexes 1–3are mononuclear and isostructural. Each metal centre is coordinated by three dihalo-substituted 8-quinolinol and two aqua ligands. The in vitrocytotoxicity of dihalo-substituted 8-quinolinol and complexes 1–3against liver cancer BEL7404 was evaluated. The IC50values of 1–3to BEL7404 were 47.2 ± 2.6, 18.3 ± 1.0 and 31.5 ± 1.2 nM, respectively. The lanthanide complexes 1–3exhibited significantly enhanced cytotoxicity vs.free substituted 8-quinolinol. The binding properties of dihalo-substituted 8-quinolinol and complexes 1and 2to DNA were investigated by UV-vis, fluorescence, CD spectroscopy and viscosity measurements, as well as agarose gel electrophoresis experiments. Both complexes 1and 2interact more strongly with DNA than the free quinolinol ligand. Intercalation is the most probable binding mode for both the complexes and the quinolinol ligands. [ABSTRACT FROM AUTHOR]

A series of apatite solid solution phosphors Ca2+xLa8−x(SiO4)6−x(PO4)xO2:Eu2+ (x = 0,2,4,6) were synthesized by a conventional high-temperature solid-state reaction. The phase purity was examined using XRD, XPS and XRF. The crystal structure information, such as the concentration, cell parameters and occupation rate, was analyzed using a Rietveld refinement, demonstrating that the Eu2+ activated the Ca2La8(SiO4)6O2 and Ca8La2(PO4)6O2 to form continuous solid solution phosphors. Different behaviors of luminescence evolution in response to structural variation were verified among the series of phosphors. Two kinds of Eu2+ ion sites were proved using low temperature PL spectra (8k) and room temperature decay curves. The substitution of large La3+ ions by small Ca2+ ions induced a decreased crystal field splitting of the Eu2+ ions, which caused an increase in emission energy from the 5d excited state to the 4f ground state and a resultant blue-shift from 508 nm to 460 nm. Therefore, with the crystal structure evolution, the emitted color of the series of phosphors could be tuned from green to blue by adjusting the ratio of Ca/La. [ABSTRACT FROM AUTHOR]