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1.
Dalton Trans ; 51(14): 5426-5433, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35311836

RESUMO

Temperature sensing plays essential roles in both fundamental research and high-tech applications. In this work, three isomorphic hexanuclear lanthanide metal-organic frameworks (Ln-MOFs), Ln(BPDC-xN) (Ln = Eu3+/Tb3+, x = 0, 1, 2) were prepared based on the cluster-based synthesis strategy with three structurally similar dicarboxylate ligands 4,4'-biphenyldicarboxylic acid (H2BPDC-0N), 6-(4-carboxyphenyl)nicotinic acid (H2BPDC-1N), and [2,2'-bipyridine]-5,5'-dicarboxylic acid (H2BPDC-2N) as the organic linkers. The as-synthesized Ln-MOFs were fully characterized using single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), elemental analysis (EA), and Fourier transform infrared spectra (FT-IR). Using a Eu3+/Tb3+ co-doping approach, Eu0.001Tb0.999(BPDC-xN) (x = 0, 1, 2) were identified as potential ratiometric luminescence thermometers. Since there are two suitable distances between the energy donors and acceptors within the framework for efficient energy transfer, all Eu0.001Tb0.999(BPDC-xN) (x = 0, 1, 2) maintain high relative sensitivity over a wide temperature range from 50 K to 300 K.

2.
Inorg Chem ; 60(10): 7345-7350, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33902276

RESUMO

Second-harmonic generation (SHG) is a kind of nonlinear optical phenomenon which has been widely used in optical devices, and factors influencing its signal are very complex. Here, taking advantage of excellent structural designability and overcoming the limitations of various coordinations of lanthanide metals, for the first time a series of lanthanide metal-organic frameworks (Ln-MOFs) with one particular ligand were synthesized and structurally characterized to study the interference of the SHG signal. The optical performance including single-photon fluorescence and SHG was collected and analyzed. It is found that all 13 kinds of Ln-MOFs can be divided into 2 crystal configurations by their individual space groups and Ln-MOFs with coordinated metal atoms from La to Tb possessing the noncentrosymmetric C2 space group exhibit the SHG property, the intensity of which depends on the type of metal atoms, the pumping wavelength, and the size of the single-crystal particles. This is the first time that the relationship between the nonlinear optical properties and the structure, metal atoms, pumping wavelength, crystal size of the whole series of Ln-MOFs is studied systematically, providing a lot of interesting results and enriching the research scope of nonlinear optics and materials science.

3.
Chem Commun (Camb) ; 57(25): 3143-3146, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33634810

RESUMO

Three different thermo-responsive fluorescent thermometers were constructed by regulating the triplet energy level of organic ligands in isostructural Eu/Tb mixed MOFs. Among them, a quite unusual and rarely reported temperature-dependent fluorescence behavior was observed in LnBDC-NH2, and Eu0.01Tb0.99NDC is effective in the physiological range with the maximum relative sensitivity of 7.32% °C-1.


Assuntos
Európio/química , Limite de Detecção , Estruturas Metalorgânicas/química , Temperatura , Térbio/química , Termometria/instrumentação
4.
Dalton Trans ; 50(8): 2792-2799, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33533347

RESUMO

Urgent demand for the prevention and diagnosis of physiological diseases is driving the development of biomarkers and physiological temperature fluorometric sensors. In this paper, a rare trinuclear lanthanide metal-organic framework (MOF), [(CH3)2NH2][Eu3(µ3-OH)(2,6-NDC)3(HCOO)3]·(solv)x (Eu(2,6-NDC), where 2,6-H2NDC = 2,6-naphthalenedicarboxylic acid) was synthesized using reticular chemistry via reducing the symmetry of the organic ligand from axisymmetric 1,4-naphthalenedicarboxylic acid (1,4-H2NDC) to non-axisymmetric 2,6-H2NDC. Eu(2,6-NDC) shows exceptional chemical and thermal stability in acid-base solutions, PBS solution, and boiling water, and even under an air atmosphere up to 300 °C. As-synthesized Eu(2,6-NDC) exhibits ratiometric detection abilities for P1,P5-di(adenosine-5') pentaphosphate (Ap5A), for use as a biomarker of dry eye disease, with a limit of detection (LOD) of 0.031 µM, as well as excellent anti-interference properties. As far as is known, it is the first Ap5A sensor based on MOFs. In addition, the results show that the ratiometric parameters of co-doped Eu0.001Gd0.999(2,6-NDC) deliver a good linear luminescence response to physiological temperatures (20-60 °C) with high sensitivity.


Assuntos
Fosfatos de Dinucleosídeos/análise , Síndromes do Olho Seco/diagnóstico , Corantes Fluorescentes/química , Elementos da Série dos Lantanídeos/química , Estruturas Metalorgânicas/química , Temperatura , Biomarcadores/análise , Humanos , Espectrometria de Fluorescência
5.
Chem Commun (Camb) ; 56(74): 10851-10854, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32812958

RESUMO

A series of isostructural Ln-MOFs, namely Eu(BPDC-xN)(x = 0, 1, 2), with different numbers of nitrogen atoms were designed and synthesized. Due to the strong affinity between the bare phosphate group of NADPH and nitrogen functional sites, the highly selective and sensitive detection of NADPH was realized. Furthermore, as the number of sites was increased, the sensitivity significantly increased, with a detection limit as low as 0.43 µM.

6.
Inorg Chem ; 59(13): 8809-8817, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32501688

RESUMO

Glutamic acid (Glu) is the most abundant excitatory neurotransmitter in the central nervous system, and an elevated level of Glu may indicate some neuropathological diseases. Herein, three isomorphic microporous lanthanide metal-organic frameworks (MOFs) [(CH3)2NH2]2[Ln6(µ3-OH)8(BDC-OH)6(H2O)6]·(solv)x (ZJU-168; ZJU = Zhejiang University, H2BDC-OH = 2-hydroxyterephthalic acid, Ln = Eu, Tb, Gd) were designed for the detection of Glu. ZJU-168(Eu) and ZJU-168(Tb) suspensions simultaneously produce the characteristic emission bands of both lanthanide ions and ligands. When ZJU-168(Eu) and ZJU-168(Tb) suspensions exposed to Glu, the fluorescence intensity of ligands increases while the emission of lanthanide ions is almost unchanged. By utilizing the emission of ligands as the detected signal and the emission of lanthanide ions as the internal reference, an internal calibrated fluorescence sensor for Glu was obtained. There is a good linear relationship between fluorescence intensity ratio and Glu concentration in a wide range with the detection limit of 3.6 µM for ZJU-168(Tb) and 4.3 µM for ZJU-168(Eu). Major compounds present in blood plasma have no interference for the detection of Glu. Furthermore, a convenient analytical device based on a one-to-two logic gate was constructed for monitoring Glu. These establish ZJU-168(Tb) as a potential turn-on, ratiometric, and colorimetric fluorescent sensor for practical detection of Glu.


Assuntos
Corantes Fluorescentes/química , Ácido Glutâmico/sangue , Estruturas Metalorgânicas/química , Neurotransmissores/sangue , Biomarcadores/sangue , Colorimetria , Európio/química , Európio/toxicidade , Corantes Fluorescentes/toxicidade , Gadolínio/química , Gadolínio/toxicidade , Limite de Detecção , Lógica , Estruturas Metalorgânicas/toxicidade , Espectrometria de Fluorescência , Térbio/química , Térbio/toxicidade
7.
Dalton Trans ; 46(23): 7549-7555, 2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28573278

RESUMO

The precise and real-time monitoring of localized pH changes is of great importance in many engineering and environmental fields, especially for monitoring small pH changes in biological environments and living cells. Metal-organic frameworks (MOFs) with their nanoscale processability show very promising applications in bioimaging and biomonitoring, but the fabrication of nanoscale MOFs is still a challenge. In this study, we synthesized a nanoscale mixed-lanthanide metal-organic framework by a microemulsion method. The morphology and size of the NMOF can be simply adjusted by the addition of different amounts of the CTAB surfactant. This NMOF exhibits significant pH-dependent luminescence emission, which can act as a self-referenced pH sensor based on two emissions of Tb3+ at 545 nm and Eu3+ at 618 nm in the pH range from 3.00 to 7.00. The MTT assay and optical microscopy assay demonstrate the low cytotoxicity and good biocompatibility of the nanosensor.

8.
Chempluschem ; 82(11): 1320-1325, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31957182

RESUMO

Luminescent temperature sensing in biological windows is uniquely superior compared to traditional temperature sensing methods because the scattering and absorption by skin, tissue and blood is minimal. In this study, the two-photon luminescence from dyes loaded into a metal-organic framework was utilised to achieve physiological temperature sensing within two biological windows. A composite was prepared that can be excited at 1064 nm to emit at 650 nm, well within the two biological windows. The two-photon luminescence intensity at 650 nm has a linear relationship with temperature over the range 20 to 60 °C. In addition, the stability and quantum efficiency were significantly improved after loading into the MOF and, with high temperature resolution, excellent repeatability and low biological toxicity, measurements with this composite has great potential to be applied to physiological temperature sensing in cells or tissues.

9.
ACS Appl Mater Interfaces ; 8(47): 32259-32265, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27933828

RESUMO

The sensing of hydrogen sulfide (H2S) has become a long-time challenging task. In this work, we developed a general strategy for sensing of H2S utilizing postsynthetic modification of a nano metal-organic frameworks (MOF) UiO-66-(COOH)2 with Eu3+ and Cu2+ ions. The nano MOF Eu3+/Cu2+@UiO-66-(COOH)2 displays the characteristic Eu3+ sharp emissions and the broad ligand-centered (LC) emission simultaneously. Because H2S can strongly increase the fluorescence of Eu3+ and quench the broad LC emission through its superior affinity for Cu2+ ions, the MOF Eu3+/Cu2+@UiO-66-(COOH)2 exhibits highly sensitive turn-on sensing of H2S over other environmentally and biologically relevant species under physiological conditions. Furthermore, this approach for fluorescent turn-on sensing of H2S is expected to extend to other water-stable MOFs containing uncoordinated -COOH.

10.
Dalton Trans ; 45(46): 18689-18695, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27830843

RESUMO

A terbium-based metal-organic framework (MOF) TbTATAB (H3TATAB = 4,4',4''-s-triazine-1,3,5-triyltri-p-aminobenzoic acid) with a 1D channel has been synthesized and structurally characterized. Then, the luminescent dye 7-diethylamino-4-methylcoumarin (C460) was encapsulated into the channel of TbTATAB by an exchange strategy to yield the dual-emitting MOF⊃dye composite TbTATAB⊃C460. Luminescence explorations demonstrated that the composite can be applied as a ratiometric thermometer over a wide temperature range from 100 to 300 K. The unique energy transfer between C460 molecules and Tb3+ enables the TbTATAB⊃C460 thermometer to be highly temperature-sensitive with a maximum relative sensitivity of 4.484% K-1 at 300 K. The composite luminescent thermometer is self-calibrated, colorimetric, reusable and much more thermosensitive than most of the other explored sensors.

11.
Chemistry ; 22(51): 18429-18434, 2016 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-27747951

RESUMO

A series of isomorphic lanthanide metal-organic frameworks (MOFs) Ln(TATAB)⋅(DMF)4 (H2 O)(MeOH)0.5 (LnTATAB, Ln=Eu, Tb, Sm, Dy, Gd; H3 TATAB=4,4',4''-s-triazine-1,3,5-triyltri-p-aminobenzoic acid) have been solvothermally synthesized and structurally characterized. Among these MOFs, TbTATAB exhibits good water stability and a high fluorescence quantum yield. Because mercury ions (Hg2+ ) have a high affinity to nitrogen atoms, and the space between multiple nitrogen atoms from triazine and imino groups is suitable for interacting with Hg2+ ions, TbTATAB shows highly selective and sensitive detection of Hg2+ in aqueous solution with a detection limit of 4.4 nm. Furthermore, it was successfully applied to detect Hg2+ ions in natural water samples.

12.
J Mater Chem B ; 4(39): 6398-6401, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263448

RESUMO

A robust zirconium-cluster-based metal-organic framework (MOF) ZJU-800 with an excellent drug loading capacity (about 58.80 wt%) has been synthesized. The system shows an adjustable release time of the drug diclofenac sodium from 2 days to 8 days by controlling the degree of compaction between MOF and drug using pressure.

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