共查询到20条相似文献,搜索用时 15 毫秒
1.
Jinping Wang Ninghai Hu Kuiyue Yang Haiyuan Zhang Chunji Niu 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(2):m52-m54
The title complex, [Gd2(C3H7NO2)4(H2O)8](ClO4)6, contains centrosymmetric dimeric [Gd2(Ala)4(H2O)8]6+ cations (Ala is α‐alanine) and perchlorate anions. The four alanine molecules act as bridging ligands linking two Gd3+ ions through their carboxylate O atoms. Each Gd3+ ion is also coordinated by four water molecules, which complete an eightfold coordination in a square‐antiprism fashion. The perchlorate anions and the methyl groups of the alanine ligands are disordered. 相似文献
2.
Rui-Juan Zhang Jian-Chao Shi Dan-Dan Zhao Xiao-Yang Han Ling Deng Xiao-Qi Cui Dan Zhao 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(11):1494-1501
A new potassium dysprosium polyborate, K3DyB6O12, has been prepared via the high‐temperature molten salt method and structurally characterized by single‐crystal X‐ray diffraction analysis. The structure can be described as a three‐dimensional framework composed of isolated bicyclic [B5O10]5? groups and Dy3+ and K+ ions. The Fourier transform IR (FT–IR) and ultraviolet–visible (UV–Vis) spectra were investigated. A series of K3Gd1–xDyxB6O12 phosphors was prepared and their photoluminescence properties were studied. The K3Gd1–xDyxB6O12 phosphors exhibit a strong yellow emission band at 577 nm (the 4F9/2→6H13/2 transition of Dy3+) under UV excitation of 275 nm (the 8S7/2→6IJ transition of Gd3+), suggesting the occurrence of the energy transfer Gd3+→Dy3+. The optimized doping concentration of the Dy3+ ion was 8 mol%. We may expect that K3Gd1–xDyxB6O12 is a promising pale‐yellow emission phosphor for visual displays or solid‐state lighting. 相似文献
3.
Prof. Gui‐Ling Wang Yong‐Mei Tian Dian‐Xue Cao Yan‐Shuang Yu Dr. Wen‐Bin Sun 《无机化学与普通化学杂志》2011,637(5):583-588
Four salen‐type lanthanide(III) coordination polymers [LnH2L(NO3)3(MeOH)x]n [Ln = La ( 1 ), Ce ( 2 ), Sm ( 3 ), Gd ( 4 )] were prepared by reaction of Ln(NO3)3 · 6H2O with H2L [H2L = N,N′‐bis(salicylidene)‐1,2‐cyclohexanediamine]. Single‐crystal X‐ray diffraction analysis revealed that H2L effectively functions as a bridging ligand forming a series of 1D chain‐like polymers. The solid‐state fluorescence spectra of polymers 1 and 2 emit single ligand‐centered green fluorescence, whereas 3 exhibits typical red fluorescence of SmIII ions. The lowest triplet level of ligand H2L was calculated on the basis of the phosphorescence spectrum of GdIII complex 4 . The energy transfer mechanisms in the lanthanide polymers were described and discussed. 相似文献
4.
Water‐soluble Gd3+‐cored poly(ether amide) dendrimer complexes, bearing a diethylenetriaminepentaacetic acid Gd3+ complex (GdDTPA) core, were synthesized. The longitudinal proton relaxivity (R1), governed mainly by the rotation correlation time of the paramagnetic Gd3+ center, was measured in water (37 °C, 20 MHz). An anchor effect at the focal point of the hydrophilic dendrimer was experimentally evaluated for the first time, through a comparison of the R1 values with the ones reported for various Gd3+ complexes, including linear copolymers of GdDTPA linked by various lengths of aliphatic chains via amide bonds. Unusually large R1 values for the first‐ and second‐generation Gd3+‐cored dendrimer complexes (6.1 and 9.3 mM?1 s?1, respectively), even with relatively low molecular weights (1355 and 3877, respectively), suggested a remarkable increase in the local rigidity around the GdDTPA core. The internal rigidity of the dendrimer was supposed to take advantage of the increased nominal molecular weight in water via multihydration to the dendron to increase the rotation correlation time, and this resulted in the observed R1 gain. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2680–2689, 2004 相似文献
5.
Efficient Luminescence from Fluorene‐ and Spirobifluorene‐Based Lanthanide Complexes upon Near‐Visible Irradiation 下载免费PDF全文
Dr. Gregorio Bottaro Dr. Fabio Rizzo Dr. Marco Cavazzini Dr. Lidia Armelao Dr. Silvio Quici 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(16):4598-4607
We describe herein the synthesis and photophysical characterization of new lanthanide complexes that consist of a (9,9‐dimethylfluoren‐2‐yl)‐2‐oxoethyl or a (9,9′‐spirobifluoren‐2‐yl)‐2‐oxoethyl unit as the antenna, covalently linked to a 1,4,7,10‐tetraazacyclododecane‐1,4,7‐triacetic acid (DO3A) unit as the Ln3+ (Gd3+, Eu3+, Sm3+, Tb3+, Dy3+) coordination site. We were able to translate the spectroscopic properties of the innovative bipartite ligands into the formation of highly luminescent europium complexes that exhibit efficient emission (?se>0.1) upon sensitization in the near‐visible region, that is, with an excitation wavelength above 350 nm. The luminescence of the Eu3+complexes is clearly detectable at concentrations as low as 10 pM . Furthermore, the structural organization of these bipartite ligands makes the complexes highly soluble in aqueous solutions and chemically stable over time. 相似文献
6.
Selective Killing of Breast Cancer Cells by Doxorubicin‐Loaded Fluorescent Gold Nanoclusters: Confocal Microscopy and FRET
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Shyamtanu Chattoraj Asif Amin Batakrishna Jana Saswat Mohapatra Dr. Surajit Ghosh Prof. Dr. Kankan Bhattacharyya 《Chemphyschem》2016,17(2):253-259
Fluorescent gold nanoclusters (AuNCs) capped with lysozymes are used to deliver the anticancer drug doxorubicin to cancer and noncancer cells. Doxorubicin‐loaded AuNCs cause the highly selective and efficient killing (90 %) of breast cancer cells (MCF7) (IC50=155 nm ). In contrast, the killing of the noncancer breast cells (MCF10A) by doxorubicin‐loaded AuNCs is only 40 % (IC50=4500 nm ). By using a confocal microscope, the fluorescence spectrum and decay of the AuNCs were recorded inside the cell. The fluorescence maxima (at ≈490–515 nm) and lifetime (≈2 ns), of the AuNCs inside the cells correspond to Au10–13. The intracellular release of doxorubicin from AuNCs is monitored by Förster resonance energy transfer (FRET) imaging. 相似文献
7.
Single‐Molecule‐Magnet Behavior in the Family of [Ln(OETAP)2] Double‐Decker Complexes (Ln=Lanthanide,OETAP=Octa(ethyl)tetraazaporphyrin) 下载免费PDF全文
Nelson Giménez‐Agulló Dr. Cristina Sáenz de Pipaón Louis Adriaenssens Dr. Marta Filibian Marta Martínez‐Belmonte Eduardo C. Escudero‐Adán Prof. Pietro Carretta Prof. Pablo Ballester Prof. José Ramón Galán‐Mascarós 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(40):12817-12825
Double‐decker complexes of lanthanide cations can be readily prepared with tetraazaporphyrins (porphyrazines). We have synthesized and characterized a series of neutral double‐decker complexes [Ln(OETAP)2] (Ln=Tb3+, Dy3+, Gd3+, Y3+; OETAP=octa(ethyl)tetraazaporphyrin). Some of these complexes show analogous magnetic features to their phthalocyanine (Pc) counterparts. The Tb3+ and Dy3+ derivatives exhibit single‐molecule magnet (SMM) behavior with high blocking temperatures over 50 and 10 K, respectively. These results confirm that, in double‐decker complexes that involve Tb or Dy, the (N4)2 square antiprism coordination mode has an important role in inducing very large activation energies for magnetization reversal. In contrast with their Pc counterparts, the use of tetraazaporphyrin ligands endows the presented [Ln(OETAP)2] complexes with extraordinary chemical versatility. The double‐decker complexes that exhibit SMM behavior are highly soluble in common organic solvents, and easily processable even through sublimation. 相似文献
8.
Über Sesquiselenide der Lanthanoide: Einkristalle von Ce2Se3 im C‐, Gd2Se3 im U‐ und Lu2Se3 im Z‐Typ
On Sesquiselenides of the Lanthanoids: Single Crystals of C‐type Ce2Se3, U‐type Gd2Se3, and Z‐type Lu2Se3 Single crystals of lanthanoid sesquiselenides (M2Se3; here: M = Ce, Gd, Lu) are accessible through conversion of the elements (lanthanoid and selenium) in molar ratios of 2:3 within seven days at 850 °C from evacuated silica ampoules if equimolar amounts of NaCl serve as a flux. In the case of Ce2Se3 (a = 897.74(6) pm) und Gd2Se3 (a = 872.56(5) pm) the cubic C‐type (I4¯3d, Z = 5.333) forms as dark red beads, whereas the orthorhombic Z‐type (Fddd, Z = 16) emerges for Lu2Se3 (a = 1125.1(1), b = 798.06(8), c = 2387.7(2) pm) as orange‐yellow bricks. Upon oxidation of monochloride hydrides (MClHx or AyMClHx; M = Ce, Gd, Lu; x = 1; A = Li, Na; y = 0.5) with selenium in arc‐welded tantalum ampoules the same main products appear with C‐Ce2Se3 and Z‐Lu2Se3, even with a surplus of NaCl or LiCl as fluxing agent. In the case of Gd2Se3, however, black‐red needles of the orthorhombic U‐type (Pnma, Z = 4; a = 1118.2(1), b = 403.48(4); c = 1097.1(1) pm) are yielded instead of C‐Gd2Se3. C‐Ce2Se3 crystallizes in a cation‐deficient Th3P4‐type structure (Ce2S3 type) according to Ce2.667□0.333Se4 (Z = 4) or with Z = 5.333 for the empirical formula Ce2Se3. Here, Ce3+ is coordinated by eight Se2— anions trigon‐dodecahedrally. In U‐Gd2Se3 (U2S3 type) two crystallographically independent Gd3+ cations with coordination numbers of 7 (Gd1) and 7+1 (Gd2), respectively, are present, exhibiting mono‐ or bicapped trigonal prisms as coordination polyhedra. The crystal structure of Z‐Lu2Se3 (Sc2S3 type) shows two different Lu3+ cations as well, which now both reside in octahedral coordination of six Se2— anions each. 相似文献
9.
Molecular‐Recognition‐Assisted pKa Shifts and Metal‐Ion‐Induced Fluorescence Regeneration in p‐Sulfonatocalix[6]arene‐Encapsulated Acridine 下载免费PDF全文
Ankita Jadhav Vrashali S. Kalyani Dr. Nilotpal Barooah Dr. Dipalee D. Malkhede Dr. Jyotirmayee Mohanty 《Chemphyschem》2015,16(2):420-427
The host–guest interactions of cationic (AcH+) and neutral (Ac) forms of the dye acridine with the macrocyclic host p‐sulfonatocalix[6]arene (SCX6) were investigated by using ground‐state absorption, steady‐state and time‐resolved fluorescence, and NMR measurements. The cationic form undergoes significant complexation with SCX6 (Keq=2.5×104 M ?1), causing a sharp decrease in the fluorescence intensity and severe quenching in the excited‐state lifetime of the dye. The strong binding of the AcH+ form of the dye with SCX6 is attributed to ion–ion interactions involving the sulfonato groups (SO3?) of SCX6 and the positively charged AcH+ at pH of approximately 4.3. Whereas, the neutral Ac form of the dye undergoes weak complexation with SCX6 (Keq=0.9×103 M ?1) and the binding constant is lowered by one order of magnitude compared with that of the SCX6–AcH+ system. The strong affinity of SCX6 to the protonated form leads to a large upward pKa shift (≈2 units) in the dye. In contrast, strong emission quenching upon SCX6 interaction and the regeneration of fluorescence intensity of the dye in the presence of Gd3+ through competitive binding have also been demonstrated. 相似文献
10.
Chao Yin Mufei Yue Pengfei Jiang Ruirui Yang Xianju Zhou Wenliang Gao Rihong Cong Tao Yang 《化学:亚洲杂志》2019,14(9):1541-1548
Searching efficient red phosphors under near‐UV or blue light excitation is practically important to improve the current white light‐emitting diodes (WLEDs). Eu2+‐ and Mn4+‐based red phosphors have been extensively studied. Here we proposed that Eu3+ is also a promising activator when it resides on a noncentrosymmetric coordination site. We proved that Cd4GdO(BO3)3 is a good host, which has a significantly distorted coordination for Eu3+. A careful crystallographic study was performed on the solid solutions of Cd4Gd1‐xEuxO(BO3)3 (0≤x≤1) by Rietveld refinements. The as‐doped Eu3+ cations locate at the Gd3+ site and are well separated by CdO8, CdO6 and BO3 groups; thus, only a slight concentration quenching was observed at ≈80 atom % Eu3+. Most importantly, the parity‐forbidden law of 4f‐4f transitions for Eu3+ are severely depressed, thus the absorptions at ≈393 and ≈465 nm are remarkable. Cd4Gd0.2Eu0.8O(BO3)3 can be pumped by a 395 nm LED chip to give a bright red emission, and when mixed with other commercial blue and green phosphors, it can emit the proper white light (0.3657, 0.3613) with a suitable Ra≈87 and correlated colour temperature ≈4326 K. In‐situ photoluminescence study indicated the low thermal quenching of these borate phosphors, especially under 465 nm excitation. Our case proves the practicability to develop near‐UV excited red phosphors in rare‐earth‐containing borates. 相似文献
11.
Doris Freiesleben Thomas Hauck Karlheinz Sünkel Wolfgang Beck Prof. Dr. 《无机化学与普通化学杂志》2007,633(7):1100-1106
Metal Complexes of Biologically Important Ligands. CLXVI Metal Complexes with Ferrocenylmethylcysteinate and 1,1′‐Ferrocenylbis‐(methylcysteinate) as Ligands A series of complexes of transition metal ions ( Cr3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+ ) and of lanthanide ions ( La3+, Nd3+, Gd3+, Dy3+, Lu3+ ) with the anions of ferrocenylmethyl‐L‐cysteine [(C5H5)Fe(C5H4CH(R)SCH2CH(NH3+)CO2?] (L1) and with the dianions of 1,1′‐ferrocenylbis(methyl‐L‐cysteine) [Fe(C5H4CH(R)SCH2CH(NH3+) CO2?)2] (R = H, Me, Ph) (L2) as N,O,S‐donors were prepared. With the monocysteine ferrocene derivative L1 as ligands complexes [MIIL12] or [CrIIIL12]Cl type complexes are formed whereas the bis(cysteine) ligand L2 yields insoluble complexes of type [ML2]n, presumably as coordination polymers. The magnetic moments of [MnIIL2]n, [PrIIIL2]n(OH)n and [DyIIIL2]n(OH)n exhibit “normal” paramagnetism. 相似文献
12.
Constructing Interfacial Energy Transfer for Photon Up‐ and Down‐Conversion from Lanthanides in a Core–Shell Nanostructure 下载免费PDF全文
Dr. Bo Zhou Dr. Lili Tao Dr. Yang Chai Prof. Shu Ping Lau Prof. Qinyuan Zhang Dr. Yuen Hong Tsang 《Angewandte Chemie (International ed. in English)》2016,55(40):12356-12360
We report a new mechanistic strategy for controlling and modifying the photon emission of lanthanides in a core–shell nanostructure by using interfacial energy transfer. By taking advantage of this mechanism with Gd3+ as the energy donor, we have realized efficient up‐ and down‐converted emissions from a series of lanthanide emitters (Eu3+, Tb3+, Dy3+, and Sm3+) in these core–shell nanoparticles, which do not need a migratory host sublattice. Moreover, we have demonstrated that the Gd3+‐mediated interfacial energy transfer, in contrast to energy migration, is the leading process contributing to the photon emission of lanthanide dopants for the NaGdF4@NaGdF4 core–shell system. Our finding suggests a new direction for research into better control of energy transfer at the nanometer length scale, which would help to stimulate new concepts for designing and improving photon emission of the lanthanide‐based luminescent materials. 相似文献
13.
Dr. Dongmei Yang Dr. Yunlu Dai Dr. Pingan Ma Dr. Xiaojiao Kang Dr. Ziyong Cheng Dr. Chunxia Li Prof. Jun Lin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(8):2685-2694
Small (2–28 nm) NaREF4 (rare earth (RE)=Nd–Lu, Y) nanoparticles (NPs) were prepared by an oil/water two‐phase approach. Meanwhile, hydrophilic NPs can be obtained through a successful phase‐transition process by introducing the amphiphilic surfactant sodium dodecylsulfate (SDS) into the same reaction system. Hollow‐structured NaREF4 (RE=Y, Yb, Lu) NPs can be fabricated in situ by electron‐beam lithography on solid NPs. The MTT assay indicates that these hydrophilic NPs with hollow structures exhibit good biocompatibility. The as‐prepared hollow‐structured NPs can be used as anti‐cancer drug carriers for drug storage/release investigations. Doxorubicin hydrochloride (DOX) was taken as model drug. The release of DOX from hollow α‐NaLuF4:20 % Yb3+, 2 % Er3+ exhibits a pH‐sensitive release patterns. Confocal microscopy observations indicate that the NPs can be taken up by HeLa cells and show obvious anti‐cancer efficacy. Furthermore, α‐NaLuF4:20 % Yb3+, 2 % Er3+ NPs show bright‐red emission under IR excitation, making both the excitation and emission light fall within the “optical window” of biological tissues. The application of α‐NaLuF4:20 % Yb3+, 2 % Er3+ in the luminescence imaging of cells was also investigated, which shows a bright‐red emission without background noise. 相似文献
14.
《化学:亚洲杂志》2017,12(12):1353-1363
Rare‐earth borates are good candidates for optical applications. To date, however, the high‐pressure/high‐temperature technique has produced a large number of novel borates with optical properties that have rarely been investigated due to the severe problem of substantial defects. We targeted the high‐pressure polymorph of β‐GdB3O6 and synthesized three solid solutions of β‐Gd0.75−x Bi0.25Tbx B3O6 (0≤x ≤0.75), β‐Gd0.75−y Bi0.25Euy B3O6 (0≤y ≤0.75), and β‐Gd0.50−z Bi0.25Tb0.25Euz B3O6 (0≤z ≤0.05) by using typical solid‐state reactions at 820 °C. Here, the function of Bi3+ is to stabilize the high‐pressure phase by lowering the synthetic temperature and being the sensitizer to promote the green and red emissions of Tb3+ and Eu3+. The multiple energy transfer paths were investigated by using lifetime decay experiments and photoluminescent spectra, and both efficiency and mechanism were determined. Eventually, color‐tunable and white emissions were achieved by rational doping of Bi3+, Tb3+, and Eu3+ into β‐GdB3O6, that is, the CIE chromaticity coordinate for β‐Gd0.44Bi0.25Tb0.30Eu0.01B3O6 is (0.318, 0.365) with a correlated color temperature of 6101 K. 相似文献
15.
《化学:亚洲杂志》2018,13(19):2834-2837
Magnetic cooling at low temperature has attracted intensive interest in cryogenics research, which may become important as cooling medium for long‐wave photon detectors to support space exploration. Here, we report a Gd‐based quaternary magnetic refrigerant material, Gd5BSi2O13, containing chains of face‐shared GdO9 polyhedra and geometrically frustrated OGd3 triangles. Magnetic measurements indicate that Gd5BSi2O13 exhibits a large magnetocaloric effect (MCE) about 1.74 times that of the practical magnetic refrigerant GGG (−ΔSm=67.0 J kg−1 K−1). We analyzed the origin of the large MCE by comparing GdIII‐containing compounds with different structures and concentrations of GdIII. 相似文献
16.
Dr. Sui‐Jun Liu Chen‐Chao Xie Ji‐Min Jia Jiong‐Peng Zhao Song‐De Han Yu Cui Yue Li Prof. Dr. Xian‐He Bu 《化学:亚洲杂志》2014,9(4):1116-1122
Four carboxylate‐bridged GdIII complexes ( 1 – 4 ) with 1D/2D structures have been synthesized by using the hydrothermal reaction of Gd2O3 with various carboxylate ligands. Compounds 1 and 2 contained the same [2n] GdIII? OH ladders, but with different crystallographically independent GdIII ions, whilst the structures of compounds 3 and 4 were composed of [Gd4(μ3‐OH)2(piv)8(H2O)2]2+ units and 1D ladder GdIII chains, respectively. Antiferromagnetic interactions occurred in compounds 1 – 3 , owing to their small Gd? O? Gd angles, whereas ferromagnetic coupling occurred in compound 4 , in which the Gd? O? Gd angles were larger. These complexes exhibited a distinct magnetocaloric effect (MCE), which was affected by their different magnetic densities and exchange interactions. Among these compounds, complex 4 presented the largest MCE (?ΔSmmax=43.6 J kg?1 K?1), the lowest Mw/NGd ratio (the highest magnetic density), and weak ferromagnetic coupling. Therefore, a lower Mw/NGd ratio and weaker exchange interactions (a smaller absolute value of θ) between GdIII ions resulted in a larger MCE for the GdIII complexes. 相似文献
17.
Hydrophobicity‐Driven Self‐Assembly of an Eighteen‐Membered Honeycomb Lattice with Almost Classical Spins 下载免费PDF全文
Guo‐Jun Zhou Prof. Dr. Johannes Richter Prof. Dr. Jürgen Schnack Prof. Dr. Yan‐Zhen Zheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(42):14846-14850
The design and synthesis of model compounds that do not exist naturally is one of the important targets in modern coordination chemistry. Herein, an eighteen‐membered honeycomb structure with equal numbers of MnII (s=5/2) and GdIII (s=7/2) metal centers has been prepared, for the first time, by using a hydrophobic force‐directed self‐assembling process. Due to the weakly coupled GdIII pairs, the magnetic properties are mainly determined by eight‐membered chains in the experimentally considered temperature range. These [Mn4Gd4] ”finite‐size“ chains, albeit with large Hilbert space, can be fully resolved by the high‐temperature series expansion and the powerful finite‐temperature Lanczos method, which reveal that the exchange‐couplings between the metal centers are antiferromagnetic and consistent with the magnetization measurement. Interestingly, from the surface‐engineering point of view, the [Mn4Gd4] chains are ”precisely“ assembled into a 2D honeycomb pattern, which is potentially desirable in the design of weakly coupled qubits. 相似文献
18.
Dora Balogh Dr. Miguel Angel Aleman Garcia Dr. H. Bauke Albada Prof. Dr. Itamar Willner 《Angewandte Chemie (International ed. in English)》2015,54(40):11652-11656
DNAzyme‐capped mesoporous SiO2 nanoparticles (MP SiO2 NPs) are applied as stimuli‐responsive containers for programmed synthesis. Three types of MP SiO2 NPs are prepared by loading the NPs with Cy3‐DBCO (DBCO=dibenzocyclooctyl), Cy5‐N3, and Cy7‐N3, and capping the NP containers with the Mg2+, Zn2+, and histidine‐dependent DNAzyme sequences, respectively. In the presence of Mg2+ and Zn2+ ions as triggers, the respective DNAzyme‐capped NPs are unlocked, leading to the “click” reaction product Cy3‐Cy5. In turn, in the presence of Mg2+ ions and histidine as triggers the second set of DNAzyme‐capped NPs is unlocked leading to the Cy3‐Cy7 conjugated product. The unloading of the respective NPs and the time‐dependent formation of the products are followed by fluorescence spectroscopy (FRET). A detailed kinetic model for the formation of the different products is formulated and it correlates nicely with the experimental results. 相似文献
19.
Wenjing Miao Lei Wang Qin Liu Shuai Guo Prof. Lingzhi Zhao Prof. Juanjuan Peng 《化学:亚洲杂志》2021,16(3):247-251
The discrimination and detection of phosphate anions have attracted extensive attention due to their important roles in various biological processes. Compared with sensors to detect one individual phosphate at a time, sensor arrays are able to discriminate multiple phosphates simultaneously. In this study, we developed a rare earth ions enhanced AuNCs-based sensor array to achieve facile and rapid identification of phosphate anions (PPi, ADP and ATP). The rare earth ions (i. e., Ce3+, Gd3+, Tm3+ and Yb3+) can significantly enhance the fluorescence of AuNCs through aggregation-induced emission effect. And the subsequent addition of phosphate anions can recover the fluorescence of the AuNCs-rare earth ions assembly. Thanks to the different numbers of phosphate group and different steric hindrance effects of phosphate anions, the recovery fluorescence of AuNCs-rare earth ions assembly induced by PPi, ADP or ATP are respectively distinct. Thus the sensor array composed of AuNCs and different rare earth ions is able to distinguish those phosphate anions. Finally, the sensor array was successfully demonstrated to identify the phosphates in blind samples. 相似文献
20.
Savarimuthu Philip Anthony 《化学:亚洲杂志》2012,7(2):374-379
2‐(2‐Hydroxy‐phenyl)‐4(3H)‐quinazolinone (HPQ), an organic fluorescent material that exhibits fluorescence by the excited‐state intramolecular proton‐transfer (ESIPT) mechanism, forms two different polymorphs in tetrahydrofuran. The conformational twist between the phenyl and quinazolinone rings of HPQ leads to different molecular packing in the solid state, giving structures that show solid‐state fluorescence at 497 and 511 nm. HPQ also shows intense fluorescence in dimethyl formamide (DMF) solution and selectively detects Zn2+ and Cd2+ ions at micromolar concentrations in DMF. Importantly, HPQ not only detects Zn2+ and Cd2+ ions selectively, but it also distinguishes between the metal ions with a fluorescence λmax that is blue‐shifted from 497 to 420 and 426 nm for Zn2+ and Cd2+ ions, respectively. Hence, tunable solid‐state fluorescence and selective metal‐ion‐sensor properties were demonstrated in a single organic material. 相似文献