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1.
Chemistry ; 30(53): e202402084, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-38975664

RESUMO

Complex oxides Eu2MeO6 (Me-Mo, W), Eu2W2O9 were obtained by a solid-phase reaction between binary oxides. The thermodynamic and kinetic mechanisms of the reaction processes were established using a variety of physical-chemical methods. All compounds obtained in this work crystallize in the low-symmetry monoclinic system, forming complex framework structures, which determine a set of very valuable physical-chemical properties. Comparison of experimental Kubelka-Munk functions and DFT- calculated absorption spectra shows adequate agreement and reveals the origin of the fundamental absorption. In addition, the deficiency in DFT calculations in the part of mutual contribution of CTBs of Mo-O and W-O, from one side, and Eu-O contributions, from the other side, is reported. Calculations of absorption spectra are shown to be superior to band structure analysis in the determination of optical band gaps. Additionally, luminescent properties of Eu2MeO6 and Eu2W2O9 compounds were investigated. These studies provide a better understanding of the electronic and optical properties of the compounds Eu2MeO6 and Eu2W2O9, along with their potential applications in various areas.

2.
Chemistry ; 30(49): e202401233, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825747

RESUMO

The reaction of Re(CO)5Br with deprotonated 1H-(5-(2,2':6',2''-terpyridine)pyrid-2-yl)tetrazole yields a triangular assembly formed by tricarbonyl Re(I) vertices. Photophysical measurements reveal blue-green emission with a maximum at 520 nm, 32 % quantum yield, and 2430 ns long-lived excited state decay lifetime in deaerated dichloromethane solution. Coordination of lanthanoid ions to the terpyridine units red-shifts the emission to 570 nm and also reveals efficient (90 %) and fast sensitisation of both Eu(III) and Yb(III) at room temperature, with a similar rate constant kET on the order of 107 s-1. Efficient sensitisation of Eu(III) from Re(I) is unprecedented, especially when considering the close proximity in energy between the donor and acceptor excited states. On the other hand, comparative measurements at 77 K reveal that energy transfer to Yb(III) is two orders of magnitude slower than that to Eu(III). A two-step mechanism of sensitisation is therefore proposed, whereby the rate-determining step is a thermally activated energy transfer step between the Re(I) centre and the terpyridine functionality, followed by rapid energy transfer to the respective Ln(III) excited states. At 77 K, the direct Re(I) to Eu(III) energy transfer seems to proceed via a ligand-mediated superexchange Dexter-type mechanism.

3.
Chemistry ; 30(33): e202400615, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38591237

RESUMO

In this work, bisarsine oxides were evaluated as novel bridging ligands, aiming to develop practical and efficient luminescent lanthanide coordination polymers. We have synthesized one-dimensional (1D) Eu3+ coordination polymers that incorporate bisarsine oxide bridging ligands and hexafluoroacetylacetonate anions. These polymers exhibited a denser packing of chains compared to analogous polymers bridged with bisphosphine oxides. The coordination polymers demonstrated exceptional thermal stability and substantial emission quantum yields. Additionally, the bisarsine oxides induced a pronounced polarization effect, facilitating a sensitive electric dipole transition that yields considerably narrow band red emission. Remarkably, the Eu3+ coordination polymers with bisarsine oxides maintained intense emission even at 550 K. A distinctive feature of these polymers is their heating-induced emission enhancement observed when the temperature was increased from 300 K to 400 K.

4.
Chemistry ; 30(27): e202400681, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38417144

RESUMO

The bulky ß-diketiminate ligand frameworks [BDIDCHP]- and [BDIDipp/Ar]- (BDI=[HC{C(Me)2N-Dipp/Ar}2]- (Dipp=2,6-diisopropylphenyl (Dipp); Ar=2,6-dicyclohexylphyenyl (DCHP) or 2,4,6-tricyclohexylphyenyl (TCHP)) have been developed for the kinetic stabilisation of the first europium (II) hydride complexes, [(BDIDCHP)Eu(µ-H)]2, [(BDIDipp/DCHP)Eu(µ-H)]2 and [(BDIDipp/TCHP)Eu(µ-H)]2, respectively. These complexes represent the first step beyond the current lanthanide(II) hydrides that are all based on ytterbium. Tuning the steric profile of ß-diketiminate ligands from a symmetrical to unsymmetrical disposition, enhanced solubility and stability in the solution-state. This provides the first opportunity to study the structure and bonding of these novel Eu(II) hydride complexes crystallographically, spectroscopically and computationally, with their preliminary reactivity investigated.

5.
J Microsc ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899727

RESUMO

The structural nature and geometry, as well as the lattice-relative orientation, of an arrangement of crystal defects in a highly textured Eu2+-doped composite of two alkali-halide solid solutions was studied by epifluorescence microscopy (EFM) using the doping ion as a fluorochrome. A three-dimensional reconstruction and a skeleton type model, as built from a sequence of EFM images of different optical cross-sections of this arrangement, are presented. Structurally, this arrangement is a quadruple node (QN) of triple junctions of grain boundaries. The QN core geometry is that of a tetragonal tristetrahedron (TTTH), centred at the QN site, whose tetrahedron vertices and edges are on the QN triple junctions and grain boundaries, respectively, whereas the tristetrahedron tetragonal axis is nearly parallel to the lattice [001]-axis. The measured values of the angles between triple junctions and between the grain boundaries forming them are reported. The distinct chemical compositions of the composite solid solutions are discussed to be responsible, in last instance, for the tristetrahedron departure from a cubic configuration. Collaterally, certain families of translationally periodic almost-parallel (TPAP)-wall-like regions which consist of TPAP-columns of TPAP-spindle-like singularities, as well as certain zigzag arrays of columns of this like, existing into the QN grains, are reported to be observed. Three-dimensional reconstructions of typical individuals of these families and arrays as well as of their constituent parts are presented and geometrically analysed. These families and arrays are discussed to be families of tilt subboundaries, whose constituent dislocations are decorated by cylindrical second-phase europium di-halide precipitates, and regularly faceted tilt subboundaries, respectively. Crystal growing and sample preparation, composite structural characterisation by powder and single-slab X-ray diffraction (PXRD and SSXRD, respectively), microscopy and fluorescence-cube unit optics, image processing, electronic three-dimensional reconstruction and measuring methodologies, are all described in detail.

6.
Photochem Photobiol Sci ; 23(2): 315-327, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38261230

RESUMO

Reaction of two equivalents of [Ln(dbm)3(H2O)] (Ln = Sm/Eu/Gd) with one equivalent of 4,4'-bipyridine (4,4'-bpy) led to the formation of rare polynuclear complexes of the type [Ln(dbm)3(4,4'-bpy)]n (dbm is the anion of 1,3-diphenyl-1,3-propanedione) instead of symmetrically bridged dinuclear complexes. The structure of the complexes has been established by the single crystal X-ray diffraction (SC-XRD) method and shows that the coordination sphere is composed of a LnO6N2 core (octacoordinated). Shape analysis further revealed that the geometry around Ln(III) is distorted square anti-prismatic with SHAPE value 0.738 and 25.719 for [Sm(dbm)3(4,4'-bpy)]n and [Eu(dbm)3(4,4'-bpy)]n, respectively. Photoluminescence (PL) properties of [Sm(dbm)3(4,4'-bpy)]n and [Eu(dbm)3(4,4'-bpy)]n are discussed in the solid-state and PMMA hybrid film (w/w 6%). By employing theoretical modelling in conjunction with the experimental PL data and crystal structure and an energy transfer (ET) mechanism for the sensitized PL of [Eu(dbm)3(4,4'-bpy)]n is proposed and discussed in detail. Finally, the role of each ligand in sensitized PL of [Eu(dbm)3(4,4'-bpy)]n is calculated and discussed by the chemical partitions of the radiative decay.Graphical abstract.

7.
Methods ; 214: 1-7, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37075873

RESUMO

Increasing awareness of the health and environment impacts of the antibiotics misuse or overuse, such as tetracycline (TC) in treatment or prevention of infections and diseases, has driven the development of robust methods for their detection in biological, environmental and food systems. In this work, we report the development of a new europium(III) complex functionalized silica nanoprobe (SiNPs-Eu3+) for highly sensitive and selective detection of TC residue in aqueous solution and food samples (milk and meat). The nanoprobe is developed by immobilization of Eu3+ ion onto the surface of silica nanoparticles (SiNPs) as the emitter and TC recognition unit. The ß-diketone configuration of TC can further coordinate with Eu3+ steadily on the surface of nanoprobe, facilitating the absorption of light excitation for Eu3+ emitter activation and luminescence "off-on" response. The dose-dependent luminescence enhancement of SiNPs-Eu3+ nanoprobe exhibits good linearities, allowing the quantitative detection of TC. The SiNPs-Eu3+ nanoprobe shows high sensitivity and selectivity for TC detection in buffer solution. Time resolved luminescence analysis enables the elimination of autofluorescence and light scattering for highly sensitive detection of TC in milk and pork mince with high accuracy and precision. The successful development of SiNPs-Eu3+ nanoprobe is anticipated to provide a rapid, economic, and robust approach for TC detection in real world samples.


Assuntos
Európio , Luminescência , Európio/análise , Európio/química , Dióxido de Silício , Tetraciclina/análise , Tetraciclina/química , Antibacterianos
8.
Anal Bioanal Chem ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261331

RESUMO

As a kind of antibiotic, tetracycline (TC) might remain in animal blood and milk products during use, which poses a risk to humans after consumption. Therefore, a ratiometric fluorescence probe was proposed for the detection of TC, which was based on an Eu3+ functionalized hydrogen-bonded organic framework (HOF). Since there are a large number of N and O atoms in the skeleton of HOF, more Eu3+ could be loaded onto HOF by forming coordinate bonds, while preserving the fluorescence of luminol monomer in HOF. In the presence of TC, the fluorescence of luminol monomer was attenuated at 425 nm due to inner filter effect (IFE), while TC selectively enhanced the fluorescence peak at 617 nm of Eu3+ under the influence of antenna effect (AE). This highly sensitive probe could detect TC in the range of 0.1-60 µM and had a low limit of detection of 8.51 nM. Besides, the HOF@Eu probe was able to detect TC in actual samples (milk and tap water) with good recoveries (95.09%-111.51%) and precision (R < 4.78%), indicating this probe has great application potential for the detection of TC in food.

9.
Luminescence ; 39(6): e4809, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890149

RESUMO

Utilizing the structure characteristic of KCaY (PO4)2 crystal, the site distribution of Eu2+ in KCaY (PO4)2:Eu phosphor coactivated with Eu2+ and Eu3+ ions is tuned. Upon 393-nm excitation, the as-prepared phosphor exhibits a broadband emission of Eu2+ peaked at ~ 475 nm and a typical red emission of Eu3+ with a strong 5D0-7F1 emission at ~ 591 nm. The luminescence color of the phosphor can be adjusted from blue to green, white, yellow, and red. The increasing concentration of Sr2+ and Eu2+ results in a blue shifting of Eu2+ emission. The increasing concentration of Eu3+ results in a red shifting of Eu2+ emission and an enhanced red emission of Eu3+. The luminescence behaviors of the phosphors are analyzed in terms of the site distribution of Eu2+ and Eu3+. A single-phase white light emitting was achieved in KCaY (PO4)2:Eu phosphor upon UV and NUV light excitation, indicating that the phosphor has potential application in white lighting.


Assuntos
Európio , Luminescência , Substâncias Luminescentes , Európio/química , Substâncias Luminescentes/química , Medições Luminescentes , Fosfatos/química
10.
Luminescence ; 39(1): e4617, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37964730

RESUMO

The atomic structure of the crystals [Eu(MBA)3 Dipy]2 (HMBA) (MBA-аnion toluic acid, Dipy-2,2'-dipyridyl, HMBA-toluic acid), displaying intensive luminescence and triboluminescence was determined using single crystal X-ray diffraction analysis. The triclinic centrosymmetric crystals have the following parameters: a = 10.620(2), b = 11.849(2), c = 14.9868(2) Å, α = 68.297(1), ß = 76.172(1), γ = 80.378(1)°, sp.gr. P - 1, Z = 1, ρcalc. = 1.537 g/cm3 . The structure belongs to the insular type and is presented as the isolated complex Eu2 -dimeric formations and outer-sphere HMBA. The structural aspects of the observed luminescence and triboluminescence properties of the compound were discussed, and the cleavage plane role in the process of the crystal destruction was revealed.


Assuntos
Acetamidas , Európio , Luminescência , Cristalografia por Raios X , Európio/química
11.
Luminescence ; 39(1): e4616, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37953062

RESUMO

Cymbopogon citratus-mediated pure aluminium oxide (Al2 O3 ) and europium (Eu)-doped Al2 O3 with different amounts of metal ion were prepared using a green synthesis method. Synthesised nanoparticles were characterised by ultraviolet (UV)-visible spectroscopy, photoluminescence (PL), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Synthesis of nanoparticles is confirmed by using UV-visible spectroscopy showing maximum absorption at 411 and 345 nm for Al2 O3 and Eu-doped Al2 O3 , respectively. The antibacterial activity of prepared nanoparticles was evaluated against Pseudomonas aeruginosa, Streptococcus aureus, Escherichia coli and Klebsiella pneumoniae using a well-diffusion technique. The effect of pure Al2 O3 and Eu-doped nanoparticles shows excellent results against P. aeruginosa, S. aureus, E. coli and K. pneumoniae.


Assuntos
Cymbopogon , Nanopartículas Metálicas , Nanopartículas , Európio/química , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana
12.
Luminescence ; 39(4): e4740, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38618664

RESUMO

A lanthanide complex based on europium (Eu) and chelidamic acid was synthesized (Eu-CHE) and characterized. The complex Eu-CHE exhibited intense luminescence at 615 nm under excitation at 300 nm and was further investigated for highly sensitive turn-off detection of l-kynurenine (l-kyn), a cancer biomarker. The probe detected l-kyn linearly from 6 nM to 0.2 µM with a limit of detection and limit of quantification of 1.37 and 4.57 nM, respectively. The probe was investigated for selectivity towards l-kyn among co-existing amino acids and further extended for detecting l-kyn from human serum and urine samples. A low-cost paper strip-based sensing platform was also developed for the visual detection of l-kyn.


Assuntos
Elementos da Série dos Lantanídeos , Neoplasias , Humanos , Cinurenina , Biomarcadores Tumorais , Neoplasias/diagnóstico , Aminoácidos , Európio
13.
Luminescence ; 39(9): e4872, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39245989

RESUMO

A highly water-soluble and fluorescent N,S-doped carbon dots/europium (N,S-CDs/Eu) was successfully synthesized via a secondary hydrothermal method. This involved surface modification of N,S-CDs derived from sunflower stem pith (SSP) with europium ions (Eu3+) doping. When excited within the range of 400-470 nm, N,S-CDs/Eu exhibited a stable and broad optimal emission wavelength ranging from 505 to 540 nm. Notably, the photoluminescence quantum yield (PLQY) of N,S-CDs/Eu is 31.4%, significantly higher than the 19.5% observed for N,S-CDs. Additionally, by dissolving N,S-CDs/Eu into polyvinyl alcohol (PVA), a uniform fluorescent anti-counterfeiting ink can be prepared. The N,S-CDs/Eu/TiO2 composite demonstrates excellent photocatalytic degradation ability towards the organic dye methylene blue (MB). N,S-CDs/Eu has potential in the field of fluorescent inks and photocatalysis due to its simple and efficient preparation and excellent properties.


Assuntos
Carbono , Európio , Helianthus , Tinta , Pontos Quânticos , Európio/química , Carbono/química , Catálise , Pontos Quânticos/química , Helianthus/química , Processos Fotoquímicos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Azul de Metileno/química , Fluorescência
14.
Mikrochim Acta ; 191(4): 172, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433173

RESUMO

A novel molecularly imprinted nanomaterial (Eu (BTC)-MPS@MIP) was synthesized on the surface of silanized europium-based metal-organic frameworks (Eu (BTC)-MPS) using 1, 3, 5-benzotrioic acid (H3BTC) as a ligand. The resulting Eu (BTC)-MPS@MIP was applied to constructing a smartphone sensing platform for the sensitive and selective detection of clothianidin (CLT) in vegetables. The synthesized Eu (BTC)-MPS@MIP demonstrated the successful formation of a typical core-shell structure featuring a shell thickness of approximately 70 - 80 nm. The developed sensing platform based on Eu (BTC)-MPS@MIP exhibited sensitivity in CLT detection with a detection limit of 4 µg/L and a linear response in the range 0.01 - 10 mg/L at excitation and emission wavelengths of 365 nm and 617 nm, respectively. The fluorescence sensing platform displayed excellent specificity for CLT detection, as evidenced by a high imprinting factor of 3.1. This specificity is primarily attributed to the recognition sites in the molecularly imprinted polymer (MIP) layer. When applied to spiked vegetable samples, the recovery of CLT ranged from 78.9 to 102.0%, with relative standard deviation (RSD) values falling between 2.2 and 6.2%. The quenching mechanism of Eu (BTC)-MPS@MIP toward CLT can be attributed to the inner filter effect (IFE), resulting from the optimal spectral overlap between the absorption spectrum of CLT and the excitation spectra of Eu (BTC)-MPS@MIP. The proposed method has the potential for extension to the detection of other pesticides by replacing the MIP recognition probes.

15.
Int J Mol Sci ; 25(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38473749

RESUMO

Cerium oxide nanoparticles (CeONPs) exhibiting antioxidant properties are investigated as potential tools for neurodegenerative diseases. Here, we synthesized polyacrylic acid conjugated cerium oxide (CeO) nanoparticles, and further to enhance their neuroprotective effect, Eu3+ was substituted at different concentrations (5, 10, 15 and 20 mol%) to the CeO, which can also impart fluorescence to the system. CeONPs and Eu-CeONPs in the size range of 15-30 nm were stable at room temperature. The X-ray Photoelectron Spectroscopy (XPS) analysis revealed the chemical state of Eu and Ce components, and we could conclude that all Eu3+ detected on the surface is well integrated into the cerium oxide lattice. The emission spectrum of Eu-CeO arising from the 7F0 → 5D1 MD and 7F0 → 5D2 transitions indicated the Eu3+ ion acting as a luminescence center. The fluorescence of Eu-CeONPs was visualized by depositing them at the surface of positively charged latex particles. The developed nanoparticles were safe for human neuronal-like cells. Compared with CeONPs, Eu-CeONPs at all concentrations exhibited enhanced neuroprotection against 6-OHDA, while the protection trend of Eu-CeO was similar to that of CeO against H2O2 in SH-SY5Y cells. Hence, the developed Eu-CeONPs could be further investigated as a potential theranostic probe.


Assuntos
Resinas Acrílicas , Cério , Nanopartículas , Neuroblastoma , Humanos , Neuroproteção , Peróxido de Hidrogênio , Nanopartículas/química
16.
Molecules ; 29(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893347

RESUMO

Glasses with the compositions in mol % of 50ZnO:(50 - x)B2O3:0.5Eu2O3:xWO3, x = 0, 1, 3, 5 and 10 were obtained by applying the melt-quenching method and investigated by Raman spectroscopy, DSC analysis and photoluminescence (PL) spectroscopy. Raman spectra revealed that tungstate ions incorporate into the base zinc borate glass as tetrahedral [WO4]2- groups, and octahedral [WØ4O2]2- species with four bridging and two non-bridging oxygen atoms. There are also metaborate, [BØ2O]- and pyroborate units, [B2O5]4-, in the glass networks. The glasses are characterized by good transmission in the visible region, at about 80%. Photoluminescence (PL) spectra evidenced that WO3 is an appropriate constituent for the modification of zinc borate glass structure and for enhancing the Eu3+ luminescent intensity. The most intense luminescence peak observed, at 612 nm, suggests that the glasses are potential materials for red emission.

17.
Molecules ; 29(15)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39125117

RESUMO

The solvothermal synthesis of LnCl3.nH2O with terephthalic acid (benzene-1,4-dicarboxylic acid, H2BDC) produced metal-organic frameworks (LnBDC), [Ln2(BDC)3(H2O)4]∞, where Ln = Sm, Eu, Tb, and Dy. The materials obtained were characterized by a number of physico-chemical techniques. The influence of the ionic radius of the lanthanides on the microstructural characteristics of the Ln-MOFs was evaluated by performing Rietveld refinement. The MOFs obtained were tested as fluorescent sensors for numerous cations and anions in water. The highly luminescent EuBDC and TbBDC demonstrated multi-responsive luminescence sensing functions to detect Ag(I), Fe(III), Cr(III), and Cr(VI), which are essential for their environmental applications. By applying the non-linear Stern-Volmer equation, the fluorescent quenching mechanism was determined. The stability of the obtained materials in water in a wide pH range (acidity pH = 4 and alkalinity pH = 9 solutions) was confirmed.

18.
Molecules ; 29(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39124962

RESUMO

New heterometallic antenna terephthalate MOFs, namely, (EuxM1-x)2bdc3·4H2O (M = Y, La, Gd) (x = 0.001-1), were synthesized by a one-step method from aqueous solutions. The resulting compounds are isomorphic to each other; the crystalline phase corresponds to Ln2bdc3∙4H2O. Upon 300 nm excitation to the singlet excited state of terephthalate ions, all compounds exhibit a bright red emission corresponding to the of 5D0-7FJ (J = 0-4) f-f transitions of Eu3+ ions. The Eu(III) concentration dependence of the photophysical properties was carefully studied. We revealed that Gd-doping results in photoluminescence enhancement due to the heavy atom effect. To quantitatively compare the antenna effect among different compounds, we proposed the new approach, where the quantum yield of the 5D0 formation is used to characterize the efficiency of energy transfer from the ligand antenna to the Eu3+ emitter.

19.
Molecules ; 29(2)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276610

RESUMO

In this work, three series of micro-sized heterometallic europium-containing terephthalate MOFs, (Eu1-xLnx)2bdc3·nH2O (Ln = La, Gd, Lu), are synthesized via an ultrasound-assisted method in an aqueous medium. La3+ and Gd3+-doped terephthalates are isostructural to Eu2bdc3·4H2O. Lu3+-doped compounds are isostructural to Eu2bdc3·4H2O with Lu contents lower than 95 at.%. The compounds that are isostructural to Lu2bdc3·2.5H2O are formed at higher Lu3+ concentrations for the (Eu1-xLux)2bdc3·nH2O series. All materials consist of micrometer-sized particles. The particle shape is determined by the crystalline phase. All the synthesized samples demonstrate an "antenna" effect: a bright-red emission corresponding to the 5D0-7FJ transitions of Eu3+ ions is observed upon 310 nm excitation into the singlet electronic excited state of terephthalate ions. The fine structure of the emission spectra is determined by the crystalline phase due to the different local symmetries of the Eu3+ ions in the different kinds of crystalline structures. The photoluminescence quantum yield and 5D0 excited state lifetime of Eu3+ are equal to 11 ± 2% and 0.44 ± 0.01 ms, respectively, for the Ln2bdc3·4H2O structures. For the (Eu1-xLux)2bdc3·2.5H2O compounds, significant increases in the photoluminescence quantum yield and 5D0 excited state lifetime of Eu3+ are observed, reaching 23% and 1.62 ms, respectively.

20.
J Sci Food Agric ; 104(4): 2120-2129, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38009620

RESUMO

BACKGROUND: Rice, a pivotal global food staple, annually accumulates vast amounts of rice husks, resulting in substantial environmental impact. Exploiting the high silica content in rice husk, our research aimed to recycle this agricultural byproduct to synthesize mesoporous silica nanoparticles (rMSNs). These nanoparticles were further modified to evaluate their potential as effective carriers for cancer drug delivery. RESULTS: rMSNs showed high biocompatibility, large surface area and porous structure as MSNs, making them excellent drug carriers. Further modifications were applied to rMSNs, such as the incorporation of the lanthanides europium and gadolinium into rMSNs, making them fluorescent and magnetic for detection and tracking using confocal fluorescence microscopy and magnetic resonance imaging. Additionally, folic acid and aptamer AS1411 were conjugated with rMSNs to enhance the targeting of cancer cells. HeLa cells exhibited higher uptake of camptothecin (CPT)-loaded rMSNs compared to normal fibroblast cells (L929). The linkage of disulfide bonds to rMSNs also allowed CPT to be carried by rMSNs and released intracellularly in the presence of the abundant reducing agent glutathione. The validation of rMSNs in vitro and in vivo proved their practical feasibility. CONCLUSION: Our findings indicate that low-cost rMSNs, derived from recycled agricultural waste, can replace highly valuable MSNs. Functionalized rMSNs exhibit promising capabilities in transporting clinical drugs to specific aberrant tissues and offering dual-targeting and dual-imaging functionalities for enhanced cancer therapy. © 2023 Society of Chemical Industry.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Oryza , Humanos , Dióxido de Silício/química , Células HeLa , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Nanopartículas/química , Porosidade , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
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