Cr掺杂镓铟酸锌长余辉纳米粒子的制备及生物传感应用

通过水热法合成了不同含量In离子掺杂的ZnGa_1.99-xIn_xO₄∶Cr_{0. 01}³⁺长余辉纳米粒子(PLNPs)。通过In掺杂和改变反应pH条件,PLNPs的余辉强度和时长明显改善,近红外余辉时间超过96h,平均粒径为15.36nm。实验结果表明,PLNPs的余辉强度被多巴胺猝灭,PLNPs的相对余辉强度(F₀-F)/F₀与多巴胺浓度在0.005～20μmol/L范围内呈良好的线性关系,线性回归线方程为y=0.1789x+0.4427,相关系数R²=0.9974,对多巴胺的检出限为0.0024μmol/L,其在生物传感领域有应用潜力。     

Recent advances in autofluorescence-free biosensing and bioimaging based on persistent luminescence nanoparticles

Persistent luminescence nanoparticles (PLNPs) refer to a series of luminescent nanomaterials that can swiftly store the excitation energy and emit persistently after ceasing the excitation. Due to the characteristics of quickly storing the excitation energy and slowly emitting luminescence for a long time after ceasing excitation, they can effectively diminish background fluorescence, and are ideal for fluorescent analysis, especially in autofluorescencefree biosensing and bioimaging.     

Recent advances in autofluorescence-free biosensing and bioimaging based on persistent luminescence nanoparticles

Persistent luminescence nanoparticles (PLNPs) are a series of emerging luminescent nanomaterials which can emit persistently after ceasing the external excitation. Due to the long decay time of persistent luminescence, the background autofluorescence in complex sample and tissues can be effectively eliminated, thus significantly improving the sensitivity of bioanalysis. Besides, such a long decay time of luminescence also makes PLNPs valuable for long-term bioimaging. Benefiting from these merits, PLNPs have been widely used for biomedical applications, especially biosensing and bioimaging. In this review, we conclude the progress in the application of PLNPs at biosensing and bioimaging in recent years, and also provide our understanding of the prospects.     

Hydrothermal synthesis of NiS nanobelts and NiS2 microspheres constructed of cuboids architectures

NiS nanobelts of hexagonal phase have been hydrothermally synthesized starting from Ni(CH₃COO)₂·4H₂O and Na₂S₂O₃·5H₂O at 200 °C for 12 h. The as-prepared nanobelts were 50 nm thick, 70-200 nm wide and more than 10 μm long. As ethylenediaminetetraacetic acid (EDTA) added, in similar condition, 2 μm NiS₂ microspheres of cubic phase were prepared. However, as Ni²⁺/ ratio was 1:1 and the temperature was decreased to 160 °C, 5 μm NiS₂ microspheres constructed of cuboids were formed.     

Thermoluminescence and synchrotron radiation studies on the persistent luminescence of BaAl2O4:Eu,Dy

The persistent luminescence materials, barium aluminates doped with Eu²⁺ and Dy³⁺ (BaAl₂O₄:Eu²⁺,Dy³⁺), were prepared with the combustion synthesis at temperatures between 400 and 600 °C as well as with the solid state reaction at 1500 °C. The concentrations of Eu²⁺/Dy³⁺ (in mol% of the Ba amount) ranged from 0.1/0.1 to 1.0/3.0. The electronic and defect energy level structures were studied with thermoluminescence (TL) and synchrotron radiation (SR) spectroscopies: UV-VUV excitation and emission, as well as with X-ray absorption near-edge structure (XANES) methods. Theoretical calculations using the density functional theory (DFT) were carried out in order to compare with the experimental data.     

Valence and environment of rare earth ions in CaAl2O4:Eu,R persistent luminescence materials

The existence of the different R²⁺/R³⁺/R^IV (R: rare earth) ions as well as the modifications in the structural environment around the dopant and co-dopants in CaAl₂O₄:Eu²⁺,R³⁺ persistent luminescence materials was studied by L_III edge X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) measurements at Hamburger Synchrotronstrahlungslabor (HASYLAB) at Deutsches Elektronen-Synchrotron (DESY) (Hamburg, Germany). The measurements were carried out at 10 and 296 K for selected rare earth (co-)dopants (Eu²⁺; Ce³⁺, Nd³⁺, Sm³⁺, and Yb³⁺).     

Hydrothermal synthesis and crystal structure of a new two-dimensional zinc citrate complex

A new two-dimensional compound C₁₂H₁₄O₁₆Zn₃ (1), containing seven-coordinate zinc atoms was prepared by the hydrothermal technique. The compound obtained was characterized by TG-DTA, single crystal X-ray diffraction, elemental analysis and FT-IR analysis. Single-crystal X-ray diffraction analysis shows that compound 1 crystallizes with monoclinic symmetry in the space group P2₁/c, a?=?6.1552(13)?Å, b?=?14.546(3)?Å, c?=?9.581?Å, β?=?102.66(2)°, V?=?836.9(4)?ų, Z?=?2, R1?=?0.0311, wR2?=?0.0830.     

Hydrothermal synthesis and structural characterization of two new reduced phosphomolybdates based on an organoamine template and copper ion

Two new compounds, (H₂en)₃(H₂enMe)₄(H₃O){Cu^I[Mo^V ₆O₁₂(OH)₃(HPO₄)(PO₄)₃]₂}?·?6H₂O (1) and (H₂enMe)₄{Cu^ICu^II[Mo^V ₆O₁₂(OH)₃(PO₄)(HPO₄)₂(H₂PO₄)]₂}?·?3H₂O (2), were hydrothermally synthesized and characterized by elemental analysis, IR, TGA, and single-crystal X-ray diffraction analysis. Crystallographic analysis reveals that 1 is constructed from cluster anions {Cu^I[Mo^V ₆O₁₂(OH)₃(HPO₄)(PO₄)₃]₂}^15?, protonated organic amines, and water molecules. Each cluster is bridged through hydrogen bonds to form a 3-D supermolecular structure. For 2, {Cu^I[Mo^V ₆O₁₂(OH)₃(PO₄)(HPO₄)₂(H₂PO₄)]₂}^11? are connected by Cu^II cations to form an infinite chain. The formation of 1 and 2 reveals that organoamines influence the structures of the crystals.     

Direct synthesis of silver/polymer/carbon nanocables via a simple hydrothermal route

High-yield silver/polymer/carbon nanocables were synthesized via a one-step simple hydrothermal route by using silver chloride and glucose as precursors. High-resolution TEM and element mapping proved that as-prepared nanocables consist of a silver nanowire core, a polymer inner shell, and a graphitic carbon outer shell. A three-step growth mechanism was proposed to explain the growth of such three-layer nanocables, i.e. the formation of silver nanowires, the glycosidation of glucose molecules on silver nanowire surface and the carbonization of the outmost glycosidation layer. We believe that reaction temperature plays the key role in the polymerization of glucose and sequent surface-carbonization.     

Coordination compounds based on CAPh type ligand: synthesis,structural characteristics and luminescence properties of tetrakis-complexes CsLnL4 with dimethylbenzoylamidophosphate

Searching for prospective luminescent materials, the series of new lanthanide coordination compounds CsLnL₄ (Ln = La, Pr, Nd, Sm – Er, and Yb; L^? = {C₆H₅CONPO(OCH₃)₂}^-) was synthesized. X-ray diffraction studies of CsNdL₄ and CsYbL₄ have been performed establishing polymeric structures of the tetrakis-complexes built from [LnL₄]^? anions and cesium cations functioning as linkers. The IR, absorption, emission, excitation spectra, and decay time measurements at 298 and 77 K, as well as thermal gravimetric analyses, were used to characterize the complexes.     

Development of a ratiometric time-resolved luminescence sensor for pH based on lanthanide complexes

Time-resolved luminescence bioassay technique using lanthanide complexes as luminescent probes/sensors has shown great utilities in clinical diagnostics and biotechnology discoveries. In this work, a novel terpyridine polyacid derivative that can form highly stable complexes with lanthanide ions in aqueous media, (4′-hydroxy-2,2′:6′,2′′-terpyridine-6,6′′-diyl) bis(methylenenitrilo) tetrakis(acetic acid) (HTTA), was designed and synthesized for developing time-resolved luminescence pH sensors based on its Eu³⁺ and Tb³⁺ complexes. The luminescence characterization results reveal that the luminescence intensity of HTTA–Eu³⁺ is strongly dependent on the pH values in weakly acidic to neutral media (pK_a = 5.8, pH 4.8–7.5), while that of HTTA–Tb³⁺ is pH-independent. This unique luminescence response allows the mixture of HTTA–Eu³⁺ and HTTA–Tb³⁺ (the HTTA–Eu³⁺/Tb³⁺ mixture) to be used as a ratiometric luminescence sensor for the time-resolved luminescence detection of pH with the intensity ratio of its Tb³⁺ emission at 540 nm to its Eu³⁺ emission at 610 nm, I_540 nm/I_610 nm, as a signal. Moreover, the UV absorption spectrum changes of the HTTA–Eu³⁺/Tb³⁺ mixture at different pHs (pH 4.0–7.0) also display a ratiometric response to the pH changes with the ratio of absorbance at 290 nm to that at 325 nm, A_290 nm/A_325 nm, as a signal. This feature enables the HTTA–Eu³⁺/Tb³⁺ mixture to have an additional function for the pH detection with the absorption spectrometry technique. For loading the complexes into the living cells, the acetoxymethyl ester of HTTA was synthesized and used for loading HTTA–Eu³⁺ and HTTA–Tb³⁺ into the cultured HeLa cells. The luminescence imaging results demonstrated the practical utility of the new sensor for the time-resolved luminescence cell imaging application.     

Ortho-platinated metallomesogens based on rod mesogenic unit of 2-phenylpyridine derivatives: synthesis,high linearly polarised and phase-state-dependent luminescence

Three series of cyclometalated platinum (II) complexes [(cbC_nppyC₁₆) Pt(acac) (a_n), (cbC_nppyC₁₆)Pt(pic) (b_n) and (cbC_nppyC₁₆)Pt(picd) (c_n)] were obtained, where cbC_nppyC₁₆ (2-(4-hexadecyloxyphenyl)-5-[(1,1?-biphenyl)-4-carbonitrile-4?-alkoxy-methoxyl]pyridine) is as cyclometalated ligand, and Hacac (acetylacetone), Hpic (picolinic acid) and Hpicd (5-[(1,1?-biphenyl)-4-carbonitrile-4?-dodecyloxy]oxy-2-car boxylpyridine) are auxiliary, respectively. The liquid crystalline behaviour, polarised emission, photophysical and phase-state-dependent luminescence properties for all platinum (II) complexes were investigated systematically. Cyclometalated platinum (II) complexes b_n show smectic phase structure; however, a_n and c_n show nematic phase. The platinum (II) complexes exhibit different photoluminescence (PL) behaviour in solution, crystal phase, liquid crystal phase and amorphous thin films. Moreover, these metallomesogens show strongly polarised photouminescence in liquid crystalline phases. Especially, the PL dichroic ratio is up to 24.6 in nenatic phase.     

Microtiterplate phosphate assay based on luminescence quenching of a terbium complex amenable to decay time detection

We describe a terbium-ligand complex (TbL) for a microtiterplate assay for phosphate (P) in the 0.3-100 μmol L⁻¹ range based on luminescence quenching. As the pH optimum is at neutral pH (7.4) the probe is quenched by both, primary (H₂PO₄⁻) and secondary phosphate (HPO₄²⁻). The LOD is 110 nmol L⁻¹. A Stern-Volmer study revealed that quenching is mostly static. Due to the ms-decay time of TbL, the first luminescence lifetime assay for phosphate could also be developed. The lifetime-based calibration plot is linear between 0.5 and 5 μmol L⁻¹ of P. The effect of various surfactants on assay performance and a study on interferents are presented. The probe was successfully applied to determination of P in commercial plant fertilizers and validated against the molybdenum blue test. The probe is the most sensitive lanthanide-based probe for phosphate.     

Two novel lanthanide(III) organic frameworks based on a biphenyltetracarboxylate ligand: synthesis,structure and magnetic and luminescence properties

Two new two‐dimensional lanthanide coordination polymers, namely poly[[tetra‐μ₂‐acetato‐tetraaquabis(μ₄‐biphenyl‐3,3′,5,5′‐tetracarboxylato)tetrakis(dimethylacetamide)tetraterbium(III)] pentahydrate], {[Tb₄(C₁₆H₆O₈)₂(C₂H₃O₂)₄(C₄H₉NO)₄(H₂O)₄]·5H₂O}_n, (1), and poly[[tetra‐μ₂‐acetato‐tetraaquabis(μ₅‐biphenyl‐3,3′,5,5′‐tetracarboxylato)tetrakis(dimethylacetamide)tetraeuropium(III)] tetrahydrate], {[Eu₄(C₁₆H₆O₈)₂(C₂H₃O₂)₄(C₄H₉NO)₄(H₂O)₄]·4H₂O}_n, (2), have been synthesized from biphenyl‐3,3′,5,5′‐tetracarboxylic acid (H₄bpt) and Ln(NO₃)₃·6H₂O (Ln = Tb and Eu) under solvothermal conditions. Single‐crystal X‐ray structure analysis shows that the two compounds are isostructural and crystallize in the monoclinic P2₁/n space group. The crystal structures are constructed from bpt⁴⁻ ligands (as linkers) and {Ln₂(μ₂‐CH₃COO)₂} building units (as nodes), which topological analysis shows to be a (4,6)‐connected network with sql topology. Compounds (1) and (2) have been characterized by elemental analysis, IR spectroscopy, powder X‐ray diffraction (PXRD), thermogravimetric analysis (TGA) and fluorescence analysis in the solid state. In addition, a magnetic investigation shows the presence of antiferromagnetic interactions in compound (1).     

The synthesis of ZnP4 based on liquid–solid reaction under high pressure and temperature

In this article we reported the successful high pressure and temperature synthesis of micron-sized zinc tetraphosphide (ZnP₄) crystals based on the liquid–solid reaction between Zn and P at a large-volume cubic press. Techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDXA) were employed to investigate the phase structure, grain size, morphology and stoichiometric ratio of crystals. The results indicate that the synthesized ZnP₄ has a tetragonal structure with the space group of P41212, and the grains with size of about 50 μm can be prepared at 4.0 GPa and 1000 °C. We also obtained the pressure–temperature (P–T) formation region of ZnP₄ and discussed the formative mechanism of ZnP₄ crystals.     

Synthesis, structure and luminescence properties of metal-organic frameworks based on benzo-bis(imidazole)

Metal-organic frameworks(MOFs)constructed from conjugated organic ligands are candidates for hybrid photoactive materials with potential applications.Compared to that from the ligands only,the intensity and wavelength of the luminescence could be tuned after they were incorporated in extended framework.In this report,by using an organic ligand with azolate moiety,benzo-bis(imidazole)(H2BBI),we synthesized two new MOF structures.Framework 1([Co(H2BBI)(DMSO)2Cl2]n,DMSO=dimethyl sulfoxide),constructed from tetrahedral Co(II)and H2BBI,exhibits zigzag 1D structure.Meanwhile,framework 2([Cu2(H2BBI)3(DMSO)6(NO3)4]n),a layered structure with hcb topology,was assembled from tetragonal pyramidal Cu(II)and H2BBI.Furthermore,2 exhibits strong luminescence emission(ex=280 nm).A blue shift of 40 nm(from 359 nm to 319 nm)was observed in framework 2 compared to the free ligand,which could be explained by the ligand-to-metal charge transfer in the network.     

Synthesis,crystal structure and luminescence of a 3-D coordination polymer based on 4-(1H-tetrazol-5-yl) benzoic acid

A cobalt(II) coordination polymer [Co(4-TZBA^2?)(H₂O)₂] (1) was obtained by treatment of Co(ClO₄)₂ · 6H₂O with 4-(1H-tetrazol-5-yl)benzoic acid [H₂(4-TZBA)] under hydrothermal conditions. The X-ray single crystal diffraction analysis reveals that 1 crystallizes in monoclinic P2₁/c, with a = 10.503(2) Å, b = 9.0860(18) Å, c = 10.179(2) Å, β = 96.75(3)° and Z = 4. In 1, adjacent cobalt(II) atoms are bridged by two 4-TZBA^2? ligands to form a dimer, which is linked with six dimers to result in a 3-D structure. 1 exhibits strong luminescence at room temperature in the solid state.     

Three-dimensional open-frameworks based on Ln(III) ions and open-/closed-shell PTM ligands: synthesis, structure, luminescence, and magnetic properties

A series of isostructural open-framework coordination polymers formulated as [Ln(dmf)(3)(ptmtc)] (Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy (5); PTMTC = polychlorotriphenylmethyl tricarboxylate) and [Ln(dmf)(2)H(2)O(αH-ptmtc)] (Ln = Sm (1'), Eu (2'), Gd (3'), Tb (4'), Dy (5')) have been obtained by treating Ln(III) ions with PTMTC ligands with a radical (PTMTC(3-)) or a closed-shell character (αH-PTMTC(3-)). X-ray diffraction analyses reveal that these coordination polymers possess 3D architectures that combine large channels and fairly rare lattice complex T connectivity. In addition, these compounds show selective framework dynamic sorption properties. For both classes of ligands, the ability to act as an antenna in Ln sensitization processes has been investigated. No luminescence was observed for compounds 1-5, and 3' because of the PTMTC(3-) ligand and/or Gd(III) ion characteristics. Conversely, photoluminescence measurements show that 1', 2', 4', and 5' emit dark orange, red, green, and dark cyan metal-centered luminescence. The magnetic properties of all of these compounds have been investigated. The nature of the {Ln-radical} exchange interaction in these compounds has been assessed by comparing the behavior of the radical-based coordination polymers 1-5 with those of the compounds with the diamagnetic ligand set. While antiferromagnetic {Sm-radical} interactions are found in 1, ferromagnetic {Ln-radical} interactions propagate in the 3D architectures of 3, 4, and 5 (Ln = Gd, Tb, and Dy, respectively). This procedure also provided access to information on the {Ln-Ln} exchange existing in these magnetic systems.     

Development of ratiometric fluorescent probe for zinc ion based on indole fluorophore

A water-soluble ratiometric fluorescent probe ZID-1 has been developed on the basis of an internal charge transfer (ICT) mechanism. Upon complexation with Zn²⁺ under physiological conditions, ZID-1 exhibits a significant blue shift of 77 nm in the emission spectrum. The fluorescent behavior of ZID-1 suggests that the pyridyl group incorporated into the fluorophore coordinates the metal ion as the fourth ligand and affords an appropriate binding affinity (K_d = 17.1 nM) for the intracellular imaging of Zn²⁺.     

Excess capacity on compound phases of Li2FeTiO4 composite cathode materials synthesized by hydrothermal reaction using optional titanium sources to boost battery performance

Li₂ FeTiO₄ composites have been produced using commercial LiAC,FeCl₂ and different titanium sources by hydrothermal synthesis(HS) at 175℃ and subsequent annealing at 700℃.Impure phase TiO₂,Fe₂ O₃ and FeTi04 were detected out among the Li2 FeTiO₄ composites with different titanium sources.Micron and nano-sized particles of Li2 FeTiO₄ were prepared from various titanium raw materials,with nano-sized particles p...