Instantaneous gelation of a new copper(II) metallogel amenable to encapsulation of a luminescent lanthanide cluster

Combining copper(II) chloride, 4-(1H-pyrazol-3-yl)pyridine and triethylamine in dimethylformamide (DMF) results in the instantaneous formation of a metallogel with as little as 0.51 wt% of gelator. The metallogel was found to encapsulate a luminescent lanthanide cluster, yielding a luminescent metallogel.     

Luminescent polymer microcapsules addressable by a magnetic field

The simultaneous encapsulation of both luminescent semiconductor and magnetic oxide nanoparticles in polymer microcapsules is demonstrated for the first time. Highly luminescent CdTe semiconductor nanocrystals serve as luminescent markers, while magnetic Fe3O4 nanoparticles allow external manipulation of the capsules by magnetic field. The method introduced is general enough to allow the fabrication of different types of multifunctional capsules in a similar way. The use of multifunctional water-compatible capsules introduced in this paper for the controlled release and directed drug delivery in biological systems is envisaged.     

Artificial luminescent protein as a bioprobe for time-gated luminescence bioimaging

An artificial luminescent protein, apoferritin-encapsulated luminescent europium complex, has been designed/fabricated and displays good biocompatibility and long-lived luminescence, which means it can be used as a bioprobe to image living cells with a time-gated mode.     

Synthesis of a Novel Blue—light—emitting Polymer Material Bearing Coumarin Pendants

A novel blue luminescent polymer bearing coumarin pendants was prepared. Its luminescent properties were determined indicating that it had strong blue fluorescent properies and good film formation ability. This novel polymer can be used as a blue organic electroluminescent material (OELM) in organic electroluminescent devices.     

Luminescent sensing of dicarboxylates in water by a bismacrocyclic dinuclear Eu(III) conjugate

The design, synthesis, and characterization of a novel dinuclear Eu(III) bismacrocyclic conjugate 1.Eu2 as a delayed luminescent lanthanide sensor for dicarboxylates is discussed. The sensor was shown to bind small dicarboxylic acids such as aspartic, malonic, succinic, or glutaric acid in pH 6.5 solutions. However, only malonic acid gave rise to selective Eu(III) luminescent enhancements, as the emission was reduced for all of the other acids.     

Multi-Color Photoluminescence Based on Mechanically and Thermally Induced Liquid-Crystalline Phase Transitions of a Hydrogen-Bonded Benzodithiophene Derivative

Controlling assembled structures of π-conjugated liquid-crystalline molecules is of great interest in the development of stimuli-responsive luminescent materials due to their molecular motility in the ordered states. Herein, we describe a mechanoresponsive hydrogen-bonded benzodithiophene liquid-crystalline molecule that exhibits a tricolor photoluminescence switching at ambient temperature. The compound shows a shear-induced phase transition from a rectangular columnar to a metastable optically anisotropic mesophase, which is accompanied by the luminescent color change from yellow to sky-blue. The metastable mesophase exhibits a time-responsive transformation to another metastable mesophase showing a blue-green emission through isothermal aging at room temperature. The luminescent color of aged sample reverts back to the initial yellow color by thermal annealing at 150 °C. These dynamic structural changes accompanied by the emission color changes are governed by distinct π-stacking modes and hydrogen-bonded patterns. The shear-induced luminescent color change from yellow to blue is found to occur above the shear strain of 390 % at which the shear stress is 2.4×10⁵ Pa as determined from dynamic viscoelastic measurements.     

Cluster Linker Approach: Preparation of a Luminescent Porous Framework with NbO Topology by Linking Silver Ions with Gold(I) Clusters

A cluster‐based luminescent porous metal–organic framework has been constructed through a “cluster linker” approach. The luminescent gold(I) cluster, prefunctionalized with pyrazinyl groups, was used as a cluster linker, similar to an organic linker, to connect silver ions in order to form a 3D framework. 1D channels with 1.1 nm diameter were observed in the framework. The cluster with its intrinsic luminescence was incorporated into a porous framework to give a luminescent bifunctional NbO net. This MOF shows solvatochromic behavior, and the interactions between solvent molecules and silver ions inside the channels account for the changes in absorption and emission spectra.     

Mechanochromic luminescent property of a polypeptide-based dendron

We report herein the mechanochromic luminescent property of a dendritic polypeptide with a fluorescent aromatic moiety at the focal point. The different luminescent property of 1 under mechanical stimulus is attributed to the switch of self-assembled structures. Moreover, the photoluminescence property of 1 also depends on the thermal history.     

An amide-containing metal-organic tetrahedron responding to a spin-trapping reaction in a fluorescent enhancement manner for biological imaging of NO in living cells

Metal-organic polyhedra represent a unique class of functional molecular containers that display interesting molecular recognition properties and fascinating reactivity reminiscent of the natural enzymes. By incorporating a triphenylamine moiety as a bright blue emitter, a robust cerium-based tetrahedron was developed as a luminescent detector of nitronyl nitroxide (PTIO), a specific spin-labeling nitric oxide (NO) trapper. The tetrahedron encapsulates molecules of NO and PTIO within the cavity to prompt the spin-trapping reaction and transforms the normal EPR responses into a more sensitively luminescent signaling system with the limit of detection improved to 5 nM. Twelve-fold amide groups are also functionalized within the tetrahedron to modify the hydrophilic/lipophilic environment, ensuring the successful application of biological imaging in living cells.     

Luminescent logic function of a surfactant-encapsulated polyoxometalate complex

We have fabricated a novel organic/inorganic hybrid material consisting of multifunctional surfactant-encapsulated polyoxometalloeuropate which functions as a luminescent logic gate with dual output operated by light and metal ion as inputs.     

Tuning solid state luminescent properties in a hydrogen bonding-directed supramolecular assembly of bis-cyclometalated iridium(III) ethylenediamine complexes

Synthesis, crystal structural determination and photophysical properties of a series of heteroleptic cationic cyclometalated iridium(III) derivatives of general formula [(ppy)(2)Ir(en)]X (X = ClO(4)(-) (1), PF(6)(-) (2), Cl(-) (3), BPh(4)(-) (4)), are described. The assembly of the common molecular building block allows to get highly luminescent crystalline materials or to assemble poorly luminescent supramolecular channelled architectures, for which the additional contribution of oxygen quenching effects has been observed. Moreover, the high reproducibility of the preparations of the crystalline materials in their specific crystalline phases, makes the control of the supramolecular organization of photo-active iridium(III) complexes within the crystalline structures a useful synthetic procedure for the construction of highly luminescent materials.     

Dual sensing of oxygen and temperature using quantum dots and a ruthenium complex

A scheme for the simultaneous determination of oxygen and temperature using quantum dots and a ruthenium complex is demonstrated. The luminescent complex [Ru(II)-tris(4,7-diphenyl-1,10-phenanthroline)]²⁺ is immobilized in a non-hydrolytic sol-gel matrix and used as the oxygen sensor. The temperature information is provided by the luminescent emission of core-shell CdSe-ZnS semiconductor nanocrystals immobilized in the same material. Measurements of oxygen and temperature could be performed with associated errors of ±2% of oxygen concentration and ±1 °C, respectively. In addition, it is shown that while the dye luminescence intensity is quenched both by oxygen and temperature, the nanocrystals luminescent emission responds only to temperature. Results presented demonstrate that the combined luminescence response allows the simultaneous assessment of both parameters using a single optical fiber system. In particular, it was shown that a 10% error in the measured oxygen concentration, induced by a change in the sample temperature, could be compensated using the nanocrystals temperature information and a correction function.     

Characterization of a Novel Intrinsic Luminescent Room‐Temperature Ionic Liquid Based on [P6,6,6,14][ANS]

Intrinsically luminescent room‐temperature ionic liquids (RTILs) can be prepared by combining a luminescent anion (more common) or cation with appropriate counter ions, rendering new luminescent soft materials. These RTILs are still new, and many of their photochemical properties are not well known. A novel intrinsic luminescent RTIL based on the 8‐anilinonaphthalene‐1‐sulfonate ([ANS]) anion combined with the trihexyltetradecylphosphonium ([P_6,6,6,14]) cation was prepared and characterized by spectroscopic techniques. Detailed photophysical studies highlight the influence of the ionic liquid environment on the ANS fluorescence, which together with rheological and ¹H NMR experiments illustrate the effects of both the viscosity and electrostatic interactions between the ions. This material is liquid at room temperature and possesses a glass transition temperature (T_g) of 230.4 K. The fluorescence is not highly sensitive to factors such as temperature, but owing to its high viscosity, dynamic Stokes shift measurements reveal very slow components for the IL relaxation.     

近红外稀土荧光在功能材料领域的研究进展

稀土近红外荧光材料具有特征发射峰尖锐、光稳定性好和毒性低等特点。近年来,稀土近红外荧光材料在光纤通讯、激光系统、生物分析传感器及生物成像等方面的应用价值日渐突显,引起了研究者们的极大关注。特别是稀土近红外荧光材料已发展成一种新兴的荧光标记材料,并有希望替代有机染料和量子点应用于生物分析和医学成像。基于稀土近红外发光的荧光探针具有低自荧光背景、宽斯托克斯位移、强抑制光漂白、深层穿透组织和短暂分辨的优势,有潜力成为高灵敏度、高选择性的检测手段。利用稀土离子制备的各种荧光材料,如上转换纳米晶、介孔材料、脂基胶体、离子液体、离子胶体、金属有机框架等,由于荧光敏化机理不同,其近红外荧光性能也各有千秋。然而,稀土近红外荧光的真正挑战仍是提高近红外发光的量子效率。本文结合近红外荧光领域的最新进展,综述了不同的稀土近红外荧光设计思路,介绍了各种近红外稀土荧光功能材料,阐述了稀土离子在近红外荧光功能材料中的优势,并展望了稀土近红外荧光材料的发展前景。     

Studies on [3]pseudorotaxane formation from a bis-azacrown derivative as host and imidazolium ion-derivatives as guest

A new host molecule, having two azacrown derivatives bridged by luminescent naphthalene diimide functionality, is found to form a [3]pseudorotaxane derivative with imidazolim ion-based guest molecules in non-polar solvents through hydrogen-bonded adduct formation. Depending upon the length of the covalent linker that links the imidazolium ion and the luminescent naphthalene fragment in the guests, the [3]pseudorotaxane adducts adopt different conformation or orientation with varying π-π/donor-acceptor interaction. The mechanism for the naphthalene-based luminescence quenching by NDI fragment on adduct formation was found to be a combination of static, as well as dynamic with static quenching as the dominant one.     

Development of a zinc ion-selective luminescent lanthanide chemosensor for biological applications

Detection of chelatable zinc (Zn(2+)) in biological studies has attracted much attention recently, because chelatable Zn(2+) plays important roles in many biological systems. Lanthanide complexes (Eu(3+), Tb(3+), etc.) have excellent spectroscopic properties for biological applications, such as long luminescence lifetimes of the order of milliseconds, a large Stoke's shift of >200 nm, and high water solubility. Herein, we present the design and synthesis of a novel lanthanide sensor molecule, [Eu-7], for detecting Zn(2+). This europium (Eu(3+)) complex employs a quinolyl ligand as both a chromophore and an acceptor for Zn(2+). Upon addition of Zn(2+) to a solution of [Eu-7], the luminescence of Eu(3+) is strongly enhanced, with high selectivity for Zn(2+) over other biologically relevant metal cations. One of the important advantages of [Eu-7] is that this complex can be excited with longer excitation wavelengths (around 340 nm) as compared with previously reported Zn(2+)-sensitive luminescent lamthanide sensors, whose excitation wavelength is at too high an energy level for biological applications. The usefulness of [Eu-7] for monitoring Zn(2+) changes in living HeLa cells was confirmed. This novel Zn(2+)-selective luminescent lanthanide chemosensor [Eu-7]should be an excellent lead compound for the development of a range of novel luminescent lanthanide chemosensors for biological applications.     

Modification of solids with polymer nanolayers as a process for manufacture of novel biomaterials

The results of study on the chemical deposition of polymeric coatings of a nanoscale thickness on porous and flat inorganic matrices and encapsulation of nano-and microparticles in polymer shells are discussed. Procedures for the deposition of homogeneous defect-free coatings are detailed by using polytetrafluoroethylene, polyaniline, and their derivatives as examples. The matrices modified with nanosized polytetrafluoroethylene and polyaniline layers are promising biomaterials for one-step isolation of nucleic acids from complex biological mixtures (cell and tissue lysates, whole blood, plant feedstock), as well as for high-performance chromatography of proteins and other biopolymers. Approaches to the fabrication of polymer shells on luminescent nanocrystals of (CdSe)ZnS via the inclusion of the nanocrystals in micrometer-sized particles based on acrolein-styrene copolymers and the formation of polymer shells directly on nanoparticles are discussed. It was shown that polymer-functionalized luminescent nanocrystals hold promise as bioanalytical reagents.     

无机纳米稀土发光材料的制备方法*

无机纳米稀土发光材料作为一种重要的发光材料,由于具有独特的光、电和化学性质,使其在高性能磁体、发光器件、显示、生物标记、光学成像和光学治疗等方面得到了广泛的应用。稀土发光材料的这些性质与材料的尺寸和形状密切相关,近年来研究者已经利用多种合成方法制备了不同形状的纳米稀土发光材料,包括纳米线、纳米棒、纳米管、纳米纤维和纳米片等。本文综述了无机纳米稀土发光材料的几种常用的制备方法,包括水热/溶剂热法、有机/无机前驱体热分解法和超声辅助合成法等,评述了这些方法的优缺点,并结合课题组在无机纳米稀土发光材料制备方面的工作,对无机纳米稀土发光材料制备方法的发展进行了展望。     

Monoradically luminescent polymers by a super acid-catalyzed polymerization and deep-red electroluminescence

Luminescent radicals have received great attention recently due to their idiographic luminescent properties and potential 100%utilization efficiency of doublets under electrical excitation. However, luminescent radical polymers are rarely explored owing to their challenging molecular design and synthesis. Herein, we report an efficient approach to construct luminescent radical polymers by a super acid-catalyzed polymerization reaction proceeded at room temperature, which intrinsically avoid the heavy metal catalyst. The obtained polymers exhibit the unique paramagnetic signals, good thermal properties, and excellent photostability. Moreover, the quantifiable electroluminescence of such radical polymers was demonstrated for the first time.     

Creation of a thermostable firefly luciferase with pH-insensitive luminescent color

The thermal instability and pH-sensitive spectral property of firefly luciferase have hampered its use as a sensitive multicolor luminescent label or bioluminescent resonance energy transfer donor. With the intention of improving the thermostability of a previously found firefly Hotaria parvula luciferase mutant with minor pH-sensitive spectral change (V368A), further mutation (E356R) was introduced by taking a reportedly stabilized mutant of Photinus pyralis luciferase into account. The double mutant E356R/V368A showed significantly improved thermostability because > 90% activity remained after incubation for 1 h at 45 degrees C, with its specific activity being maintained. Unlike the wild type or V368A, E356R/V368A showed no change in the emission maximum of 568 nm even at pH 6.3, also implying a mutual relationship between thermostability and the proportion of yellow-green luminescent peak under acidic condition.