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1.
Whether rare earth elements can enter into plant cells remains controversial. This article discusses the ultracellular structural
localization of lanthanum (La3+) and europium (Eu3+) in the intact plant cells fed by rare earth elements Eu3+ and La3+. Eu-TTA fluorescence analysis of the plasmalemma, cytoplast, and mitochondria showed that Eu3+ fluorescence intensities in such structures significantly increased. Eu3+ can directly enter or be carried by the artificial ion carrier A23187 into plant cells through the calcium ion (Ca2+) channel and then partially resume the synthesis of amaranthin in the Amaranthus caudatus growing in the dark. Locations of rare earth elements La3+ and Eu3+ in all kinds of components of cytoplasmatic organelles were determined with transmission electron microscope, scanning electron
microscope, and energy-dispersive X-ray microanalysis. The results of energy-dispersive X-ray microanalysis indicated that
Eu3+ and La3+ can be absorbed into plant cells and bind to the membranes of protoplasm, chloroplast, mitochondrion, cytoplast, and karyon.
These results provide experimental evidence that rare earth elements can be absorbed into plant cells, which would be the
basis for interpreting physiological and biochemical effects of rare earth elements on plant cells. 相似文献
2.
Wen‐Xian Li Yu‐Shan Zheng Wen‐Juan Chai Tie Ren Yu Liu Ying‐Jie Li Xiao‐Jun Sun Gao‐Wa Xing 《Luminescence》2011,26(6):754-761
A novel ternary complex, TbL5L′(ClO4)3·3H2O, two binary complexes, TbL7(ClO4)3·3H2O and TbL′3.5(ClO4)3·4H2O has been synthesized (using diphenyl sulphoxide as the first ligand L, bipyridine as the second ligand L′). Their composition was analysed by element analysis, coordination titration, IR spectra and 1H‐NMR, and the fluorescence emission mechanism, fluorescence intensities and phosphorescence spectra were also investigated by comparison. It was shown that the ternary rare‐earth complex showed stronger fluorescence intensities than the binary rare‐earth complexes in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 8.23 times, 3.58 times as strong as that of the binary systems TbL7(ClO4)3·3H2O and TbL′3.5 (ClO4)3·4H2O, respectively. By fluorescence analysis it was found that both diphenyl sulphoxide and bipyridine could sensitize the fluorescence intensities of rare‐earth ions. In particular, in the ternary rare‐earth complex, introduction of bipyridine was of benefit to the fluorescence properties of Tb(III). Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
3.
Pragya Pandit Shailendra Kumar Manoj Mohapatra Pargin Bangotra Rohit Mehra A.K. Singh 《Luminescence》2019,34(2):212-221
In the current study, the structural and spectroscopic properties of phosphatic shale samples obtained from the Atomic Minerals Directorate for Exploration and Research were probed for potential use as a phosphor material. X‐ray diffraction and Raman and Fourier transform infrared spectroscopy revealed that the beneficiated phosphatic shale samples were primarily monophasic consisting of fluorapatite [Ca5(PO4)3F, (FAP)] with minor traces of haematite (α‐Fe2O3) and calcite (CaCO3). Energy dispersive X‐ray fluorescence revealed the presence of U, Eu, Dy and Tb in the FAP matrix substituted at Ca(I) and Ca(II) sites of FAP. A reduced optical direct band gap of 4.46 eV was calculated from the Tauc plot. Photoluminescence spectral studies revealed multicolour emissions (red, yellow, green and blue) on ultraviolet light excitation that were attributed to luminescence spectra from rare earth ions Eu3+, Tb3+, U4+ and U6+ in the FAP matrix. The overall emissions for the rare earth and actinide‐doped FAP were obtained in the cool white region and the corresponding Commission Internationale de l’Eclairage chromaticity coordinates were calculated to be (0.274, 0.317). The corresponding colour correlated temperature obtained was 9342 K. Furthermore, phosphatic shale had a high room temperature dielectric constant of 11 at a frequency of 1 kHz that demonstrated its suitability for use in biological sensors. The study showed that natural phosphatic shale could be a potential material for optical, biological and dielectric applications. 相似文献
4.
The luminescence of novel rare earth ( Tb 3 + , Eu 3 + and Dy 3 + )‐activated Ba 2 Sr 2 Al 2 O 7 phosphors for solid‐state lighting is presented. The aluminate phosphors were synthesized using a one‐step combustion method. X‐Ray diffraction, scanning electron microscopy and photoluminescence characterizations were performed to understand the mechanism of excitation and the corresponding emission in the as‐prepared phosphor, as characterized the phase purity and microstructure. Improvements in the luminescence properties of the phosphors with rare earth concentration were observed. The phosphor hue could be tuned from blue, green and red by proper selection of rare earth ions in typical concentrations. Effective absorption in the near‐ultraviolet region was observed, which makes the phosphor a potential candidate for ultraviolet light‐emitting diodes. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
5.
Nanocrystallines of rare earth complex, Eu(TTA)3·3H2O, were synthesized by the chemical precipitation method and were characterized by elemental analysis, ultraviolet visible absorption spectroscopy (UV–vis), infrared spectroscopy (IR), differential thermal analysis–thermogravimetry (TG‐DTA), X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The size of the nanocrystallines was tunable by selecting the proper buffer system, which was used to control the pH of the solution. A small polydispersity in particle size ranging from 70 to 250 nm was obtained when ammonia was used. The nanocrystallines showed the characteristic fluorescence of europium ions and energy transfer from the organic ligand to central ions was observed by fluorescence excitation and emission spectroscopy. These nanoparticles of rare earth complexes have potential application in luminescent materials due to their excellent fluorescence properties. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
6.
Fluorescence enhancement of europium (III) perchlorate by 1,10‐phenanthroline on the 1‐(naphthalen‐2‐yl)‐2‐(phenylsulthio)ethanone complex and luminescence mechanism
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Wen‐Xian Li Xiao‐Dong Xin Shu‐Yan Feng Yu Liu Jing Zhang Bo‐Yang Ao Ying‐Jie Li 《Luminescence》2014,29(7):810-817
A novel ligand, 1‐(naphthalen‐2‐yl)‐2‐(phenylsulthio)ethanone was synthesized using a new method and its two europium (Eu) (III) complexes were synthesized. The compounds were characterized by elemental analysis, coordination titration analysis, molar conductivity, infrared, thermo gravimetric analyzer‐differential scanning calorimetry (TGA‐DSC), 1H NMR and UV spectra. The composition was suggested as EuL5 · (ClO4)3 · 2H2O and EuL4 · phen(ClO4)3 · 2H2O (L = C10H7COCH2SOC6H5). The fluorescence spectra showed that the Eu(III) displayed strong characteristic metal‐centered fluorescence in the solid state. The ternary rare earth complex showed stronger fluorescence intensity than the binary rare earth complex in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 1.49 times as strong as that of the binary system. The phosphorescence spectra were also discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
7.
Tm3+:LaF3 nanocrystals were synthesized with hydrothermal technique. Local‐field effect on the radiative relaxation rate was studied in the system of Tm3+:LaF3 nanocrystals immersed in several liquid media. The fluorescence lifetime was measured. It was found that the fluorescence decay presented the characteristics of second‐order exponential decay, for which the contribution from the ions inside the nanocrystal and ions at the interface of the nanocrystal were distinguished. Investigating the experimental results with proposed models, we found that the surface effect had to be eliminated. For rare earth doped LaF3 nanocrystals, real‐cavity model well explains the influence of surrounding medium on the fluorescence relaxation rate. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
8.
Nd3+, La3+ and Ce3+ at proper concentrations had positive effects on the cell growth of Arnebia euchroma and production of shikonin derivatives. A mixture of rare earth elements (MRE, La2O3:CeO2:Pr6O11: Sm2O3 = 255:175:3:1, mol/mol) behaved the most remarkable effects. Two-stage culture was used for the cell proliferation and the
biosynthesis of shikonin derivatives. After 20 days culture, 0.05 mM MRE gave the highest cell biomass (24.8 g dry weight l−1), which was 98.0% higher than that without rare earth elements. Similarly, when 0.05 mM MRE was added to the biosynthesis
medium, the highest content (8.9% dry weight) and production (571.1 mg l−1) of shikonin derivatives were obtained, which were 89.4% and 165.3% higher than those without rare earth elements, respectively.
The increase of the cell biomass and shikonin derivatives may due to increasing the activities of peroxidase and phenylalanine
ammonia lyase caused by the addition of the rare earth elements. 相似文献
9.
Shuaishuai Yang Zuping Guo Wei Huang Zhongqian Hu Guizhi Li Dongcai Guo 《Luminescence》2022,37(4):588-597
Four novel coumarin fluorescence small-molecules were successfully prepared and validated by proton nuclear magnetic resonance (1H-NMR), carbon-13 (13C)-NMR, and mass spectrometry (MS). Their corresponding europium(III) complexes were synthesized and characterized. The ligand can emit green fluorescence in solutions, and the best concentration was 40 μmol/L. The emission peak of ligand has a red-shift with the increase of concentration and solvent polarity. And the effect of various substituents in ligand was ordered using fluorescence intensity as standard: - NO2 > -Cl > -OCH3 > -OH. The order of fluorescence quantum yield is in line with the order of fluorescence intensity. The title europium complexes exhibit red fluorescence of europium ion (Eu3+) with good thermal stability. The effect of various substituents in ligand on the fluorescence intensity of title europium complexes was also consistent with the earlier results. This suggests that the prepared coumarins fluorescence small-molecules and their corresponding europium complexes have potential application prospects in the field of optical materials. 相似文献
10.
Callus cultures of Saussurea medusa were cultivated on solid culture medium supplemented with either Ce3+, La3+, Nd3+ or a mixture of rare earth elements. Ce3+, 0.05 mM, gave the highest biomass (0.53 g dry wt per flask) and total flavonoids (27.5 mg per flask), which were, 70% and 100% higher than those without Ce3+ addition, respectively. Ce3+, 0.01–0.1 mM, or La3+, 0.05 mM, or the mixture of rare earth elements, 0.025–0.1 mM, can substitute for 6-benzyladenine, and 0.025 mM Ce3+ can partly substitute for naphthaleneacetic acid in promoting cell growth and biosynthesis of total flavonoids in S. medusa. 相似文献
11.
A new system for the determination of nucleic acid by rare earth metallic porphyrin of [tetra‐(3‐methoxy‐4‐hydroxyphenyl)]–Tb3+ [T(3‐MO‐4HP)–Tb3+] porphyrin as fluorescence spectral probe has been developed in this paper. Nucleic acid can enhance the fluorescence intensity of the T(3‐MO‐4HP)–Tb3+ porphyrin in the presence of bis(2‐ethylhexyl)sulfosuccinate sodium salt(AOT) micelle. In pH 8.00 Tris–HCl buffer solution, under optimum conditions, the enhanced fluorescence intensity is in proportion to the concentration of nucleic acids in the range of 0.05–3.00 µg mL?1 for calf thymus DNA (ct DNA) and 0.03–4.80 µg mL?1 for fish sperm DNA(fs DNA). Their detection limits are 0.03 and 0.01 µg mL?1, respectively. In addition, the binding interaction mechanism between T(3‐MO‐4HP)–Tb3+ porphyrin and ct DNA is also investigated by resonance scattering and fluorescence spectra. The maximum binding number is calculated by molar ratio method. The new system can be used for the determination of nucleic acid in pig liver, yielding satisfactory results. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
12.
《Bioorganic & medicinal chemistry》2014,22(7):2045-2051
The designing and development of fluorescent chemosensors have recently been intensively explored for sensitive and specific detection of environmentally and biologically relevant metal ions in aqueous solution and living cells. Herein, we report the photophysical results of alanine substituted rhodamine B derivative 3 having specific binding affinity toward Fe3+ with micro molar concentration level. Through fluorescence titration at 599 nm, we were confirmed that ligand 3 exhibited ratiometric fluorescence response with remarkable enhancement in emission intensity by complexation between 3 and Fe3+ while it appeared no emission in case of the competitive ions (Sc3+, Yb3+, In3+, Ce3+, Sm3+, Cr3+, Sn2+, Pb2+, Ni2+, Co2+, Cu2+, Ba2+, Ca2+, Mg2+, Ag+, Cs+, Cu+, K+) in aqueous/methanol (60:40, v/v) at neutral pH. However, the fluorescence as well as colorimetric response of ligand–iron complex solution was quenched by addition of KCN which snatches the Fe3+ from complex and turn off the sensor confirming the recognition process was reversible. Furthermore, bioimaging studies against L-929 cells (mouse fibroblast cells) and BHK-21 (hamster kidney fibroblast), through confocal fluorescence microscopic experiment indicated that ligand showed good permeability and minimum toxicity against the tested cell lines. 相似文献
13.
矿区复合污染土壤真菌多样性及其对稀土-重金属离子的吸附特征 总被引:2,自引:0,他引:2
大量的稀土-重金属通过尾矿坝的浮尘、地表径流和渗滤液排放到周边土壤中,影响了土壤中的微生物群落结构。【目的】分析稀土和重金属复合污染土壤真菌群落结构并分离具有同时吸附稀土和重金属的菌株。【方法】本研究基于ITS基因,采用Illumina-Hiseq测序技术分析了包头稀土尾矿坝周边5份稀土-重金属污染土壤样品和距尾矿区20 km的1份相对未受污染的土壤样品的真菌群落特征,同时采用富集培养法从污染样品中筛选出金属耐性真菌,并对其进行吸附稀土-重金属的特性分析。【结果】群落结构为:在门水平,除了未分类门真菌(unclassified Fungi)外,子囊菌门(Ascomycota)真菌在所有土壤中占比较大(13.5%–90.5%);在纲水平上,除了未分类纲真菌外,粪壳菌纲(Sordariomycetes)真菌在B2 (73.1%)、B3 (28.4%)和B4 (20.8%)的丰度显著高于对照样点C (7.4%),而座囊菌纲(Dothideomycetes)在B5 (11.8%)的丰度明显高于B1 (3.5%);在属水平,除了未分类属,足孢子虫属(Podospora)是C(0.9%)和B3(23.6%)样点的优势种。曲霉属(Aspergillus)、未分类的格孢腔菌目(unclassified Pleosporales)和未分类的戴维迪科(unclassified Davidiellaceae)分别为B1 (3.0%)、B4 (10.5%)和B5(5.8%)的优势种,而蜡蚧属(Lecanicillium)真菌只在B2样点土壤存在且占优(51.6%)。Zn污染对真菌群落结构的影响大于稀土元素污染,且其浓度与优势的未分类真菌相对丰度呈负相关。从污染样品中共分离出6株真菌,它们分属于曲霉属(Aspergillus)(5株)和镰刀霉菌属(Fusarium)(1株)。所有分离菌株对镧(La~(3+))的吸附率均显著高于锌(Zn~(2+)),其中Aspergillus sp. B6-3对La~(3+)和锌Zn~(2+)的吸附率最高,分别为19.7%和3.9%。【结论】该研究为利用真菌去除稀土和重金属以优化生物吸附过程导向的环境生物修复和保护策略提供了机制基础。 相似文献
14.
Liu C Hong FS Tao Y Liu T Xie YN Xu JH Li ZR 《Biological trace element research》2011,143(2):1110-1120
The mechanism of the molecular interaction between Ce3+, a member of rare earth elements, and Rubisco in vitro is investigated. The carboxylase activity of Rubisco greatly increased
under low concentrations of Ce3+ and decreased under high concentrations of Ce3+. The ultraviolet absorption spectra show that the various concentrations of Ce3+ treatment do not shift the characteristic peaks of Rubisco while the characteristic peak intensity of Rubisco increases with
increasing Ce3+ concentration. The Rubisco–Ce3+ interactions also do not cause any noticeable change in the λmax of Rubisco fluorescence spectra. However, the fluorescence
intensity of Rubisco is found quenched by the addition of Ce3+, which strongly suggests that Ce3+ could directly bind to the Rubisco protein. and the binding sites is estimated to 1.52 per protein. The binding between Ce3+ and Rubisco is also proved by extended X-ray absorption fine-structure essay; Ce3+ coordinated with eight oxygen atoms of Rubisco in first shells and six oxygen atoms in second shells. The results implied
that Ce3+ might improve the microenvironment of Rubisco and, in turn, affected the carboxylase capacity of Rubisco greatly. 相似文献
15.
Salhah D. Al-Qahtani Razan M. Snari Kholood Alkhamis Nada M. Alatawi Mona Alhasani Samar Y. Al-nami Nashwa M. El-Metwaly 《Luminescence》2022,37(3):479-489
Long-persistent phosphorescent smart paints have the ability to continue glowing in the dark for a prolonged time period to function as energy-saving products. Herein, new epoxy/silica nanocomposite paints were prepared with different concentrations of lanthanide-doped aluminate nanoparticles (LAN; SrAl2O4:Eu2+,Dy3+). The LAN pigment was firstly coated with silicon dioxide (SiO2) utilizing the heterogeneous precipitation technique to provide LAN-encapsulated between SiO2 nanoparticles (LAN@SiO2). The epoxy/silica/lanthanide-doped aluminate nanoparticles (ESLAN) nanocomposite paints were coated on steel. The prepared ESLAN paints were studied by transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray fluorescence (XRF) analysis, and energy-dispersive X-ray spectroscopy (EDS). The transparency and coloration properties of the nanocomposite coated films were explored by CIE Lab parameters and photoluminescence spectra. The ultraviolet-induced luminescence properties of the transparent coated films demonstrated greenish phosphorescence at 518 nm upon excitation at 368 nm. Both hardness and hydrophobic activities were investigated. The anticorrosion activity of the nanocomposite films coated onto mild steel substrates immersed in aqueous sodium chloride (NaCl(aq)) (3.5%) was studied by electrochemical impedance spectroscopy (EIS). The silica-containing coatings were monitored to exhibit anticorrosion properties. Additionally, the nanocomposite films with LAN@SiO2 (25%) exhibited the optimized long-lasting luminescence properties in the dark for 90 min. The nanocomposite films showed highly reversible and durable long-lived phosphorescence. 相似文献
16.
Novel water‐soluble green fluorescent carbon nanodots (CNs) using methacrylic acid and m‐phenylenediamine as precursors were first synthesized using a one‐pot hydrothermal method. Red fluorescent lanthanide complexes were prepared using lanthanide ion Eu3+ and pyridine‐2,6‐dicarboxylic acid. The optical properties of CNs were characterized using ultraviolet visible (UV) spectra and fluorescence spectra, microscopic morphology was characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS), and the elemental composition was characterized using Fourier transform‐infrared spectroscopy (FT‐IR) and X‐ray photoelectron spectra (XPS). The fluorescence spectra of the lanthanide complexes were also measured. A simple strategy was developed to prepare UV light‐tunable fluorescent inks and polymer hydrogels films based on CNs and lanthanide complexes. The fluorescent inks and polymer hydrogels films could be repeatedly switched between green and red fluorescence. The change of color depended on luminescence of the CNs and the lanthanide complexes under 254 and 365 nm UV light, respectively. The UV light‐tunable fluorescent inks and polymer hydrogels films could enhance its anti‐counterfeiting function for data and information. 相似文献
17.
Ludmila Chistoserdova 《Molecular microbiology》2019,111(5):1127-1131
Recently, rare‐earth elements lanthanides (Ln3+) have emerged as enzyme cofactors of methanol dehydrogenases of the XoxF type. It is now understood that XoxF enzymes can functionally replace the alternative, calcium‐dependent, MxaFI‐type methanol dehydrogenases, when Ln3+ are available. These rare‐earth metals are not only essential for XoxF activity, but they also regulate gene expression, in a reverse fashion, activating the expression of XoxF and repressing the expression of MxaFI. This type of regulation has created multiple conundrums, including the details of the solubility, transport, sensing and selection mechanisms for Ln3+ by the bacterial cells, as well as the questions relevant to the evolution of the alternative enzymes and their potentially different redox properties. Overall, the newly discovered biological activity of Ln3+ presents a big puzzle. Ochsner et al. add several pieces to this puzzle, utilizing a model phyllosphere colonizer Methylobacterium extorquens PA1. They determine that Ln3+ sensing by this organism can take place via both XoxF‐dependent and XoxF‐independent mechanisms. They also identify genes for a TonB‐dependent transporter and an ABC‐type transporter and demonstrate that both are essential for Ln3+‐dependent methanol metabolism. The puzzle still requires multiple additional pieces for completion, but great strides have been made toward the goal of solving it. 相似文献
18.
Proton relaxation rate and fluorometric studies of manganese and rare earth binding to concanavalin A 总被引:1,自引:0,他引:1
The binding of Mn2+, Ca2+, and rare earth ions to apoconcanavalin A has been studied by water proton relaxation enhancement, electron paramagnetic resonance spectroscopy, and fluorescence spectroscopy. An electron paramagnetic resonance and water proton relaxation rate study of the titration of apoconcanavalin A with Mn2+ gives evidence of two equivalent binding sites per monomer with KD = 50 μm ± 4 μm. When a similar Mn2+ titration of apoconcanavalin A is performed in the presence of Ca2+ ion, very little free Mn2+ is detected by electron paramagnetic resonance until the two Mn2+ binding sites per monomer are filled. The substitution of a rare earth ion for Ca2+ ion in the above experiment often resulted in a slight displacement of Mn2+ from the transition metal site as detected by electron paramagnetic resonance. A water proton relaxation rate study of the titration of apoconcanavalin A with Gd3+ reflects two binding sites with a KD = 40 μm ± 4 μm and two with a KD = 200 μm ± 50 μm. The fluorescence emission spectrum of concanavalin A (λem = 340 nm) is slightly quenched by the addition of Tb3+ while Tb3+ fluorescence is greatly enhanced. A fluorometric titration of apoconcanavalin A with Tb3+ also reflects two sites with a KD = 40 μm ± 15 μm and two with a KD = 270 μm ± 50 μm. 相似文献
19.
Liu Xiaoqing Huang Hao Liu Chao Zhou Min Hong Fashui 《Biological trace element research》2009,130(2):141-151
Photosystem II (PSII) from Arabidopsis thaliana treated by lanthanum (La3+), cerium (Ce3+), and neodymium (Nd3+) were isolated to investigate the effects of 4f electron characteristics and alternation valence of rare earth elements (REEs)
on PSII function regulation comparatively. Results showed that REE treatment could induce the generous expression of LhcII b in A. thaliana and increase the content of light-harvesting complex II and its trimer on the thylakoid membrane significantly. Meanwhile,
the light absorption in the red and blue region and fluorescence quantum yield near 683 nm were obviously increased; oxygen
evolution rate was greatly improved too, suggesting that REEs could enhance the efficiency of light absorption, regulate excitation
energy distribution from photosystem I (PSI) to PSII, and thus increase the activity of photochemical reaction and oxygen
evolution accordingly. The efficiency order of the four treatments was Ce3+ > Nd3+ > La3+ > control. 相似文献
20.
为提高藏红花(Crocus sativus)胚性愈伤组织的繁殖系数与出芽率, 以建立藏红花离体快繁体系, 解决其资源短缺问题, 采用两步法, 用稀土调控其胚性愈伤组织的生长与分化。结果表明, 在添加了0.25 mg·L–1 NAA、3 mg·L–1 6-BA和400 mg·L–1 CH的B5固体培养基中, 0.04 mmol·L–1 La3+促进胚性愈伤组织生长的效果最佳, 繁殖系数为12, 是不添加稀土处理组的1.48倍; 在添加了0.25 mg·L–1 NAA、3 mg·L–1 6-BA和400 mg·L–1 CH的1/2 B5固体培养基中, 0.06 mmol·L–1 Ce3+促进胚性愈伤组织分化出芽的效果最佳, 出芽率高达84.5%, 是不添加稀土处理组的1.81倍, 且高于国外报道的出芽率(40%)。初步解决了藏红花胚性愈伤组织生长慢和出芽率低等问题, 为建立高效稳定的藏红花离体快繁体系奠定了基础。 相似文献