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Research has been conducted on the heterodinuclear complexes. The synthesis of the d-f heterodinuclear Gd(III)-Ni(II) cryptate has been carried out and the results indicate that Gd(III)-Ni(II) interact ferromagnetically.

A facile approach, a ball-milling reaction method, is used to design and regulate the fabrication of 14 dinuclear and 2-D cyano-bridged 4f-3d hexacyanometallates. Diamagnetism along with isomorphous structures of the [Co.sup.3+] and [La.sup.3+] ions provide an estimate of the nature of coupling between the iron (III) and lanthanide(III) ions in the [La.sup.3+]- [Fe.sup.3+] complexes.

The synthesis, crystal and band structures, and optical properties of a new quaternary cadmium and mercury pnictidehalide, (Hg2Cd2As2Br)Br, are reported. The electronic band structure along with the density of states (DOS) calculated by the density functional theory (DFT) method has shown that compound (Hg2Cd2As2Br)Br is a semiconductor with an indirect band gap and that the optical absorption mainly originates from the charge transitions from the Br2-4p and As-4p to Cd-5s and Hg-6s states.

Transition metal complex [[Mn[(2,2'-bipy).sub.2]].sup.2+] is incorporated into thioarsenate, resulting in the formation of two novel compounds, [[Mn.sub.3][(2,2'-bipy).sub.3][([As.sup.V][S.sub.4]).sub.n].n[H.sub.2]O] and [[Mn.sub.2][(2,2'-bipy)[As.sub.2.sup.III][S.sub.5]. The main-group chalcogenide framework is incorporated in these compounds with a [[tm[(2,2'-bipy).sub.m].sup.n+] complex.

We successfully developed an effective strategy for preparing poly(butylene succinate) (PBS) material with exceptionally high crystallinity (94.4% from density data) and melting point (~136 °C) from its urea inclusion complex under normal air pressure for the first time. The strategy consists of three steps: co-electrospinning PBS with urea, thermal treatment, and coalescence of PBS in water. Electrospinning provides well physical mixing between PBS and urea. Thermal treatment causes the assembly of PBS and urea and leads to formation of their inclusion complex, in which PBS chains are separately isolated in urea channels. During the coalescing process the isolated and ordered PBS chains formed crystals with lamellar thickness larger than 26 nm-larger than 5-fold of common PBS crystal-after removing host urea frames. PBS crystals obtained with such high crystallinity and melting point are proved to be the extended-chain crystals (ECCs). Comparative study reveals that the electrospinning and thermal treatment process are necessary in this strategy for preparation of ECC although many other methods can be also used to obtain inclusion complex. Further study shows that the strategy is also feasible for obtaining ECCs of other aliphatic polyesters. [ABSTRACT FROM AUTHOR]

Bionanoparticles and nanostructures with high biocompatibility and stability, low toxicity, diversification of imaging modality, and specificity of targeting to desired organs or cells are of great interest in nanobiology and medicine. However, integrating all of these desired features into a single bionanoparticle, which can be applied to biomedical applications and eventually in clinical prediagnosis and therapy, is still a challenge. We herein report a facile one-step solvothermal approach to fabricate targetable and biocompatible β-NaYF4:Yb,Gd,Tm upconversion nanoparticles (UCNPs) with bimodal-signals (near-infrared (NIR) fluorescence and magnetic resonance (MR) signals) using hyaluronic acid (HA) as a multifunctional molecule. The prepared UCNPs with low toxicity are successfully applied for in vitro and in vivo targeted tumor imaging. The developed biomimetic surface modification approach for the synthesis of biomolecule-guided multifunctional UCNPs holds great potential applications in medical diagnostics and therapy. [ABSTRACT FROM AUTHOR]

Near infrared (NIR)-emitting persistent luminescent nanoparticles (PLNPs) have great potential for in vivo bioimaging with the advantages of no need for in situ excitation, high signal-to-noise ratio, and deep tissue penetration. However, functional NIR-emitting PLNPs with long afterglow for long-term in vivo imaging are lacking. Here, we show the synthesis of NIR-emitting long-persistent luminescent nanoparticles ( LPLNPs ) Zn2.94Ga1.96Ge2O10:Cr3+,Pr3+ by a citrate sol-gel method in combination with a subsequent reducing atmosphere-free calcination. The persistent luminescence of the LPLNPs is significantly improved via codoping Pr3+/Cr3+ and creating suitable Zn deficiency in zinc gallogermanate. The LPLNP powder exhibits bright NIR luminescence in the biological transparency window with a superlong afterglow time of over 15 days. A persistent energy transfer between host and Cr3+ ion in the LPLNPs is observed and its mechanism is discussed. PEGylation greatly improves the biocompatibility and water solubility of the LPLNPs. Further bioconjugation with c(RGDyK) peptide makes the LPLNPs promising for long-term in vivo targeted tumor imaging with low toxicity [ABSTRACT FROM AUTHOR]

The simplicity of the green-synthesized routine and the availability of surface modification of diverse bioactive molecules make noble metal nanostructures highly suitable as multifunctional biomaterials for biological and biomedical application. Here, we report the preparation of trypsin stabilized gold nanoclusters (try-AuNCs) with near-infrared fluorescence for biosensing heparin based on surface plasmon enhanced energy transfer (SPEET) and folic acid (FA) modified try-AuNCs for in vivo cancer bioimaging. The SPEET/try-AuNCs fluorescence biosensor was designed via heparin mediated energy transfer between try-AuNCs and cysteamine modified gold nanoparticles (cyst-AuNPs). The developed SPEET/try-AuNCs fluorescence biosensor allowed sensitive and selective detection of heparin with a linear range of 0.1-4.0 µg mL-1 and a detection limit (3s) of 0.05 µg mL-1. The relative standard deviation for eleven replicate detections of 2.5 µg mL-1 heparin was 1.1%, and the recoveries of the spiked heparin in human serum samples ranged from 97% to 100%. In addition, folic acid was immobilized on the surface of try-AuNCs to ameliorate the specific affinity of AuNCs for tumors, and the near-infrared fluorescent FA-try-AuNCs were applied for in vivo cancer imaging of high folate receptor (FR) expressing Hela tumor. In vivo study of the dynamic behavior and targeting ability of FA-try-AuNCs probe to Hela tumor bearing mice and normal nude mice validated the high specific affinity of FA-try-AuNCs probe to FR positive tumors. The results show that the prepared try-AuNCs have great potential as multifunctional biomaterials for biosensing biomolecules with SPEET mode and in vivo cancer imaging with high targeting ability. [ABSTRACT FROM AUTHOR]

Transferrin (Tf)-functionalized gold nanoclusters (Tf-AuNCs)/graphene oxide (GO) nanocomposite (Tf-AuNCs/GO) was fabricated as a turn-on near-infrared (NIR) fluorescent probe for bioimaging cancer cells and small animals. A one-step approach was developed to prepare Tf-AuNCs via a biomineralization process with Tf as the template. Tf acted not only as a stabilizer and a reducer but also as a functional ligand for targeting the transferrin receptor (TfR). The prepared Tf-AuNCs gave intense NIR fluorescence that can avoid interference from biological media such as tissue autofluorescence and scattering light. The assembly of Tf-AuNCs and GO gave the Tf-AuNCs/GO nanocomposite, a turn-on NIR fluorescent probe with negligible background fluorescence due to the super fluorescence quenching property of GO. The NIR fluorescence of the Tf-AuNCs/GO nanocomposite was effectively restored in the presence of TfR, due to the specific interaction between Tf and TfR and the competition of TfR with the GO for the Tf in Tf-AuNCs/GO composite. The developed turn-on NIR fluorescence probe offered excellent water solubility, stability, and biocompatibility, and exhibited high specificity to TfR with negligible cytotoxicity. The probe was successfully applied for turn-on fluorescent bioimaging of cancer cells and small animals. [ABSTRACT FROM AUTHOR]

The self-assembly reactions of Ln(NO 3) 3·aq (Ln = La, Nd, Sm, Gd, Dy, Er, and Yb) with K 3[Fe(CN) 6] and three monosulfoxide ligands, dimethylsulfoxide (DMSO), diethylsulfoxide (DESO), and tetramethylene sulfoxide (TMSO), respectively, in water give rise to three series of 21 Ln III−Fe IIIcomplexes with ten kinds of compositions and structures: cis-[Fe(CN) 4(μ-CN) 2La(H 2O) 3(DMSO) 3] n· nH 2O ( 1), [Fe(CN) 5(μ-CN)Ln(H 2O) 3(DMSO) 4]·H 2O [Ln = Nd ( 2), Dy ( 5)], [Fe(CN) 5(μ-CN)Ln(H 2O) 4(DMSO) 3]·H 2O [Ln = Sm ( 3), Gd ( 4)], trans-[Fe(CN) 4(μ-CN) 2Ln(H 2O)(DMSO) 4] n[Ln = Er ( 6), Yb ( 7)], [Fe(CN) 6][La(H 2O) 6(DESO) 3] ( 8), trans-[Fe(CN) 4(μ-CN) 2Ln(H 2O) 4(DESO) 2] n·2 nH 2O [Ln = Nd ( 9), Sm ( 10), Gd ( 11), Dy ( 12), Er ( 13)], cis-[Fe(CN) 4(μ-CN) 2Yb(H 2O) 3(DESO) 2] n·2 nH 2O ( 14), [Fe(CN) 5(μ-CN)Ln(H 2O) 3(TMSO) 4]·1.5H 2O [Ln = La ( 15), Nd ( 16), Gd ( 18)], cis-[Fe(CN) 4(μ-CN) 2Sm(H 2O) 4(TMSO) 2] n( 17) and cis-[Fe(CN) 4(μ-CN) 2Ln(H 2O) 3(TMSO) 2] n· nH 2O [Ln = Dy ( 19), Er ( 20), Yb ( 21)]. The X-ray structure analyses show that 2− 5, 15, 16, and 18have cyano-bridged dinuclear structures; 1, 6, 7, 9− 14, 17, and 19− 21form one-dimensional (1D) chain structures; but 8is an ionic compound without cyano-bridging. For those complexes with 1D structure, there are also different configurations ascribed to the cis- or trans-coordination of bridging CN −moieties to the Fe IIIion. The coordination of two CN −moieties to one Ln IIIion is all- trans(N−Ln−N > 90°), mainly due to the steric effect of Fe(CN) 63−entities. Further, such complexes feature extensive O−H···O and O−H···N hydrogen bonds that give rise to different three-dimensional (3D) supramolecular structures and stabilize and influence these structures. The differences of composition and structure of these complexes may be attributed to the structural differences of the three monosulfoxide blocking ligands, as well as different lanthanide ions to some extent, although a general rule (or underlying relationship) can not be deduced. [ABSTRACT FROM AUTHOR]

Two structural series, including seven isomorphous heterodinuclear complexes, [Ln(DMSO)4(H2O)3(μ-CN)M(CN)5]·H2O ([La-Fe] (1), [Pr-Fe] (2), [Pr-Co] (3), [Nd-Fe] (4), [Nd-Co] (5), [Sm-Fe] (6) and [Sm-Co] (7)), and seven isostructural 2-D stairlike cyano-bridged bimetallic assemblies, [Ln(DMSO)2(H2O)(μ-CN)4M(CN)2]n ([La-Fe]n (8), [Pr-Fe]n (9), [Pr-Co]n (10), [Nd-Fe]n (11), [Nd-Co]n (12), [Sm-Fe]n (13) and [Sm-Co]n (14)) (DMSO = dimethylsulfoxide), have been rationally prepared by a facile approach, a ball-milling method, and characterized by X-ray diffraction and magnetic measurements. The isomorphous structures, in conjunction with the diamagnetism of the Co3+ and La3+ ions, allow an approximation to the nature of coupling between the iron(lll) and lanthanide(lll) ions in the Ln3+-Fe3+ complexes. The Ln3+-Fe3+ interaction is ferromagnetic for the dinuclear [Pr-Fe] (2), [Nd-Fe] (4), and [Sm-Fe] (6) systems and for the 2-D [Pr-Fe]n (9), [Nd-Fe]n (11), and [Sm-Fe]n (13) assemblies. [ABSTRACT FROM AUTHOR]

Ten compounds of the IIB metal halide/pseudohalide-bipy system, -ZnBr2(4,4‘-bipy)n(1), Cd2Br5(4,4‘-bipyH)2(CdBr3) (2), Cd3Br6(4,4‘-bipy)n(3), CdI2(4,4‘-bipy)n(4), (HgI2)2(4,4‘-bipy) (5), Hg(CN)2(4,4‘-bipy)(H2O)2n(6), HgCl2(2,2‘-bipy) (7), HgCl2(2,2‘-bipy)·2HgCl2(8), Hg3Br6(2,2‘-bipy)·HgBr2(9), and HgI2(2,2‘-bipy)·HgI2(10), have been synthesized via hydro(solvo)thermal and solid-state reactions; except for 4, all the other compounds are reported for the first time. Compound 1features a 1-D zigzag chain, based on tetrahedral zinc atoms bridged by 4,4‘-bipy molecules and terminally coordinated by two bromine atoms. The chains are linked by hydrogen bonds and ··· interactions to form a 2-D sheet. Compound 2possesses dinuclear Cd2Br5(4,4‘-bipyH)2cations and CdBr3-anions. Compound 3has a 2-D layered structure, constructed from novel triple chains and bridging 4,4‘-bipy ligands. The triple chains contain edge-shared CdBr6and CdBr5N octahedra. In 4, the layers are formed by monochains and bridging 4,4‘-bipy molecules. The monochains contain edge-shared CdI4N2octahedra. Compound 5features a discrete structure with a 4,4‘-bipy ligand bridging two HgI2moieties. Compound 6has a 1-D zigzag chain, containing octahedral mercury atoms and bridging 4,4‘-bipy molecules. In 7and 8, mercury atoms are tetrahedrally coordinated to two chlorine atoms and two nitrogen atoms. In 9, 2-, 3-, 4-, and 5-coordinated mercury atoms coexist, whereas in 10, the mercury atoms are only 2- and 4-coordinated. Photoluminescence investigations reveal that the compounds display strong emissions in the blue/green/yellow regions, which, in combination with the molecular orbital (MO) calculations of 1, 5, and 7, leads us to conclude that the emissions originate from a ligand-to-ligand charge-transfer (LLCT) transition. The solid-state diffuse reflectance spectra, IR, and TG-DTA are also presented. [ABSTRACT FROM AUTHOR]

Four cyano-bridged 4f−3d (lanthanide−transition metal) bimetallic assemblies, Sm(DMF)2(H2O)3(-CN)3M(CN)3n·nH2O (M Fe (1), Co (2)) with 2-D monolayered structures and Sm(DMF)(H2O)3(-CN)4M(CN)2n·nH2O (M Fe (3), Co (4)) with 2-D bilayered structures (DMF N,N-dimethylformamide), were rationally prepared by a facile approach, a ball-milling method, and characterized by X-ray diffraction studies and magnetic measurements. The unprecedented 2-D bilayered 4f−3d hexacyanometalates (3and 4) were obtained by controllably reducing the half amount of DMF in the reactive system in comparison with 1and 2through a ball-milling method. [ABSTRACT FROM AUTHOR]