查找使用阿拉丁产品的科研文献

A SPR aptamer sensor for mercury based on AuNPs@NaYF4:Yb,Tm,Gd upconversion luminescent nanoparticles

Bo Ling,Yuanhui Ma,Hongqi Chen,Lun Wang

A new aptamer-based surface plasmon resonance (SPR) system has been designed to detect Hg2+ that utilizes near-infrared (NIR)-to-NIR gold nanoparticle coated NaYF4:Yb,Tm,Gd up-conversion nanoparticles (AuNPs@NaYF4:Yb,Tm,Gd UCNPs) as probes. The AuNPs@NaYF4:Yb,Tm,Gd UCNPs were prepared and excited by near-infrared light (980 nm) which emitted at a near-infrared wavelength (808 nm) using an inexpensive infrared continuous wave laser diode. The AuNPs@NaYF4:Yb,Tm,Gd UCNPs were conjugated with Hg2+ aptamers. In the presence of Hg2+, the AuNPs@NaYF4:Yb,Tm,Gd UCNPs were brought into close proximity because of the formation of T–Hg2+–T base pairs. Then the luminescence enhanced because of the plasmon resonance effects. Based on this, a new SPR system was developed for the detection of Hg2+ that had high sensitivity and selectivity in the NIR region. This method was successfully applied to detect Hg2+ concentration in real samples.

Strong Structural Modification of Gd to Co3O4 for Catalyzing N2O Decomposition under Simulated Real Tail Gases

Ying Xiong,Yumei Zhao,Xingkun Qi,Jiayi Qi,Yuanyuan Cui,Haibiao Yu,Ying Cao

In this paper, Gd-promoted Co3O4 catalysts were prepared via a facile coprecipitation method for low-temperature catalytic N2O decomposition. Due to the addition of Gd, the crystallite size of Co3O4 in the Gd0.06Co catalyst surprisingly decreased to 4.9 nm, which is much smaller than most additive-modified Co3O4 catalysts. This huge change in the catalyst’s textural structure endows the Gd0.06Co catalyst with a large specific surface area, plentiful active sites, and a weak Co–O bond. Hence, Gd0.06Co exhibited superior activity for catalyzing 2000 ppmv N2O decomposition, and the temperature for the complete catalytic elimination of N2O was as low as 350 °C. Meanwhile, compared with pure Co3O4, Ea decreased from 77.4 to 46.8 kJ·mol–1 and TOF of the reaction increased from 1.16 × 10–3 s–1 to 5.13 × 10–3 s–1 at 300 °C. Moreover, Gd0.06Co displayed a quite stable catalytic performance in the presence of 100 ppmv NO, 5 vol % O2, and 2 vol % H2O.

Efficient and selective recovery of Gd(III) via polyethyleneimine modification of lanthanum-based metal–organic frameworks

Wenhao Li,Lijinhong Huang,Bin Xiao,Xiaoguang Duan,Haike Li,Lang Li,Wanfu Huang

With the development of the economy and the increasing demand for environmental protection, the efficient and selective recovery of Gd(III) from actual wastewater is of critical importance. In this work, lanthanum-based metal–organic framework (LaBDC) materials were prepared by a hydrothermal method, and then polyethyleneimine (PEI) and LaBDC were combined by an impregnation method to form a novel LaBDC@ x PEI composite. The prepared materials were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Experiments show that LaBDC@50%PEI has the highest adsorption capacity (181.77 mg/g) among lanthanum-based MOFs with different PEI loadings at pH = 5.5, which is about 5.1 times that of bare LaBDC. The adsorption isotherm analysis shows that LaBDC@50%PEI follows the Langmuir model. In addition, the adsorption kinetics of LaBDC@50%PEI follows a pseudo-second-order kinetic model, indicating that the adsorption process is chemical adsorption. It is worth noting that LaBDC@50%PEI maintains good adsorption performance and stability after three recycling tests, and exhibits excellent selectivity in cation interference experiments. Overall, the LaBDC@50%PEI composites possess good stability and hold great promises in rapid recovery of Gd(III) from practical aqueous environments.

Wavelength-shift-based visual fluorescence sensing of aspartic acids using Eu/Gd-MOF through pH triggering

Xiaohui Wen,Chenghui Li,Zexi Zhou,Yujing He,Juan He,Xiandeng Hou

With the increasing demand for on-site detection, the current approach of building dual-emission or multi-emission luminescence sensors based on metal-organic frameworks (MOFs) which possess the capacity of self-reference for numerous non-analyte factors falls short of meeting sensing requirements. Therefore, we have designed a novel strategy for constructing wavelength shift-based luminescence sensor named Eu/Gd(TCPP), which exhibits dual-emitting from metal ions Eu 3+ and flexible rotating aggregation-induced emission (AIE) ligands H 4 TCPP (2,3,5,6-tetrakis(4-carboxyphenyl)pyrazine). This sensor was prepared by a simple, green and fast plasma synthesis method. It's worth noting that the fluorescence emission of Eu/Gd(TCPP) shows a specific wavelength shift from ligand peak, and a visual color change from red to blue within a pH range of 4 to 3. Moreover, various characterization data verified that the luminescence switching mechanism of Eu/Gd(TCPP) was attributed to the H + -induced collapse of the Eu/Gd(TCPP) crystal structure, followed by untwisting of free ligands that lose rigid MOFs confinement. This hindered the antenna effect from H 4 TCPP to Ln 3+ ions and restricted the rotation emission of ligand, resulting in the red-shifting of the ligand emission and corresponding luminescence switching. By tactfully utilizing the short-range pH response property of Eu/Gd(TCPP), highly sensitive and selective on-site visual detection of acidic aspartic acid can be achieved.

Ag2S quantum dot-based magnetic resonance/fluorescence dual-mode imaging nanoprobes for tumor diagnosis

Jia-Hua Zou,Li-Li Chen,Yong-Guo Hu,Dong Zhou,Yong Li,Bin Zhang,Xin-Yue Xu,Bo Liu,Jin-Xuan Fan,Yuan-Di Zhao

Accurate tumor detection is crucial for the early discovery and subsequent treatment of small neoplastic foci. Molecular imaging, which combines non-invasiveness, high specificity, and strong sensitivity, excels in diagnosing early tumors and stands out among tumor diagnosis methods. Here, we introduced a dual-modal imaging probe capable of actively targeting tumor cells, suitable for both near-infrared (NIR) fluorescence and magnetic resonance imaging (MRI). Dendritic mesoporous silica was used as a carrier for the probe, encapsulating Ag2S quantum dots (QDs) for NIR fluorescence imaging. Additionally, the probe conjugated the MRI contrast agent Gd-DOTA and cetuximab, which targeted EGFR on the tumor cell membrane surface, to achieve dual-modal imaging in the tumor area. This strategy provided a methodology for the accurate diagnosis of early-stage tumor lesions and guides precise lesion resection during surgery, offering significant potential for clinical application.

A liposomal curcumol nanocomposite for magnetic resonance imaging and endoplasmic reticulum stress-mediated chemotherapy of human primary ovarian cancer

Jing Wang,Yonghong Song,Mingxun Zhang,Zhensheng Wu,Yun-Jun Xu,Jun Lin,Daishun Ling,Youjing Sheng,Yang Lu,Qiang Wu

Combination chemotherapy has improved the life quality of patients suffering from ovarian cancer; however, drug resistance and late relapse lead to a high mortality rate. As a bioactive component in zedoary oil, curcumol has been widely used against gynecological tumors in the clinic. However, the bioavailability of curcumol is limited by its indissolubility in water. The design of nano-formulas is promising to improve traditional drugs in the clinic, which is beneficial for the treatment of malignant diseases, especially cancer. Herein, a liposomal curcumol nanocomposite was prepared for the theranostics of human primary ovarian cancer cells from solid tumor tissue in patients. In this uniform nanocomposite, curcumol and a frequently used magnetic resonance contrast agent, gadopentetate dimeglumine (Gd-DTPA), were effectively wrapped in the hydrophobic lipid bilayer and aqueous cavity of the liposome, respectively. Parallel assessments of the anti-tumor ability and mechanism of liposomal curcumol were performed on both SKOV3 and human primary ovarian cancer cells, and the results indicated the induction of apoptosis in ovarian cancer cells by this curcumol nanocomposite via the endoplasmic reticulum pathway. Liposomal curcumol has been further confirmed to inhibit the growth of SKOV3 human ovarian cancer xenografts on tumor-bearing nude mice. Moreover, this gadolinium-based liposomal curcumol nanocomposite exhibited excellent T1-weighted magnetic resonance imaging (MRI) capability for the efficient detection of xenograft ovarian cancer, leading to a novel multifunctional therapeutic agent.

Rational design of high performance nanotheranostics for NIR-II fluorescence/magnetic resonance imaging guided enhanced phototherapy

Qi Wang,Jie Cai,Xinrui Niu,Jing Wang,Jiawei Liu,Chen Xie,Wei Huang,Quli Fan

Nanotheranostics, which can provide great insight into cancer therapy, has been deemed as a promising technology to settle the unmet medical needs. The rational design of high performance nanotheranostics with multiple complementary imaging features and satisfactory therapeutic efficacy is particularly valuable. Herein, versatile nanotheranostic agents DPPB-Gd-I NPs were fabricated by using gadolinium-diethylenetriaminepentaacetic acid chelates and an iodine-decorated copolymer as encapsulation matrixes to encapsulate a polymer DPPB through one-step nanoprecipitation. We have demonstrated that such nanoagents are able to efficiently damage tumors under single dose injection and NIR laser illumination conditions due to the enhanced photodynamic therapy and enhanced photothermal therapy (the tumor inhibition rate was as high as 94.5%). Moreover, these nanoagents can be utilized as dual-modal NIR-II fluorescence/magnetic resonance imaging probes for tumor diagnosis with high sensitivity, deep tissue penetration, and excellent spatial resolution. Overall, this work offers a powerful tactic to fabricate high performance nanotheranostics for clinical application.

A family of quasi-one-dimensional zigzag spin-chain Ba2REV3O11 (RE = Pr, Nd, and Gd–Ho) compounds

Jin Zhou,Tong Shi,Ri-Tao Huang,An-Di Liu,Gao-Shang Gong,Yong-Qiang Wang,Lang-Sheng Ling,Jing-Xin Li,Yu-Yan Han,Wei Tong,Zheng-Cai Xia,Zhao-Ming Tian

The diverse exotic magnetic states realized in one-dimensional (1D) spin-chain systems have motivated the extensive exploration of new materials with a 1D spin-chain motif, while 1D magnets comprising rare-earth (RE) ions are largely unexplored compared with their 3d transition metal (TM)-based counterparts. Herein, we report the synthesis and magnetic properties of a family of RE-based zigzag spin-chain Ba2REV3O11 compounds (RE = Pr, Nd, and Gd–Ho) crystallized into a monoclinic structure with the space group P21/a, wherein spin chains are connected by edge-sharing REO6 octahedra along the b axis and well separated by nonmagnetic VO4 tetrahedra extended within the ac plane. Moreover, the nearest neighbor (NN) intrachain RE–RE distance (dintra, ∼3.856–3.952 Å) is much shorter than the NN interchain separation (dinter, ∼5.191–5.246 Å), supporting quasi-1D characteristics. Magnetic susceptibility and isothermal magnetization measurements revealed that only Ba2DyV3O11 displays a magnetic anomaly at ∼2.9 K and other family members do not order down to 1.8 K. Among them, Ba2GdV3O11 with a spin-only magnetic moment (S) of 7/2 exhibits a long-range magnetic order with TN ∼ 0.67 K and a large magnetocaloric effect with a maximum magnetic entropy change (ΔSM) of 14.3 J K−1 (mol-Gd)−1 under a magnetic field change (Δμ0H) of 4 T at a temperature of ∼1 K, making it a suitable material for magnetic refrigeration in sub-Kelvin temperature regimes.

Tunable NIR emission in Cr3+ activated (La,Gd)Sc3(BO3)4 based on host crystal engineering strategy

Honglei Yuan,Huizhong Ma,Gaoliang Wang,Huanxia Jia,Liwei Wang

This study systematically investigates the structural and luminescent characteristics of LaSc 3 (BO 3 ) 4 :x %Cr 3+ and La (1-y) Gd y Sc 3 (BO 3 ) 4 :1.0 %Cr 3+ phosphors. X-ray diffraction confirms the formation of a pure hunter-type structure for all samples, with Cr 3+ occupying Sc 3+ sites and Gd 3+ substituting La 3+ , inducing lattice contraction. Luminescent analysis reveals that LaSc 3 (BO 3 ) 4 :Cr 3+ exhibits an emission at 980 nm under 430 nm excitation, attributed to the 4 T 2 → 4 A 2 transition of Cr 3+ in a weak crystal field. The substitution of Gd 3+ enhances photoluminescence intensity by 2.15-fold, and blue-shifts emission to 938 nm because of increased crystal field splitting and structural rigidity. The broadened full width at half maximum is also formed due to the enhanced degree of disorder in GdSc 3 (BO 3 ) 4 . Thermal stability studies show that GdSc 3 (BO 3 ) 4 :Cr 3+ retains 49 % intensity at 540 K, outperforming LaSc 3 (BO 3 ) 4 :Cr 3+ (41 %), supported by higher activation energy (ΔE = 0.338 eV vs. 0.296 eV). The improved thermal resistance is linked to lattice rigidity and reduced electron-phonon coupling. NIR-pc-LEDs fabricated with GdSc 3 (BO 3 ) 4 :Cr 3+ demonstrate superior radiant flux (68.7 mW at 200 mA) compared to La-based devices. These results highlight the critical role of host lattice engineering in optimizing Cr 3+ luminescence for high-power NIR applications.

KRE(CO3)2 (RE = Eu, Gd, Tb): new mixed metal carbonates with strong photoluminescence and large birefringence

Yuan Lin,Chun-Li Hu,Zhi Fang,Jin Chen,Wei-Jie Xie,Yan Chen,Jian-Pu Wang,Jiang-Gao Mao

Three new potassium rare earth carbonates, namely KRE(CO3)2 (RE = Eu, Gd, Tb), were synthesized successfully. Their structures feature a novel [RE(CO3)2]− 3D framework with 1D channels along the c axis filled with K+ cations. Among them, KEu(CO3)2 and KTb(CO3)2 emit strong red and green photoluminescence, respectively. The birefringence values of KRE(CO3)2 were measured as 0.149, 0.162 and 0.215 at 546 nm, respectively. Remarkably, KTb(CO3)2 has the largest experimental birefringence among carbonates reported.

Glypican-1-antibody-conjugated Gd–Au nanoclusters for FI/MRI dual-modal targeted detection of pancreatic cancer

Xin Huang,Chengqi Fan,Huanhuan Zhu,Wenjun Le,Shaobin Cui,Xin Chen,Wei Li,Fulei Zhang,Yong Huang,Donglu Sh,Zheng Cui,Chengwei Shao,Bingdi Chen

Quaternary Noncentrosymmetric Rare-Earth Sulfides Ba4RE2Cd3S10 (RE = Sm, Gd, or Tb): A Joint Experimental and Theoretical Investigation

Qing-Gang Yue,Sheng-Hua Zhou,Bingxuan Li,Xin-Tao Wu,Hua Lin,Qi-Long Zhu

Multinary rare-earth chalcogenides with d-block transition metals have attracted considerable attention owing to their intriguing structural architectures and promising practical applications. In this work, three quaternary rare-earth sulfides, Ba4RE2Cd3S10 (RE = Sm, Gd, or Tb), have been obtained by the high-temperature solid-state method. These compounds are isostructural and belong to the noncentrosymmetric orthorhombic space group Cmc21 (No. 36). The basic structural unit contains unique two-dimensional anionic [RE2Cd3S10]8– layers, which are separated by Ba2+ cations. Remarkably, Ba4Sm2Cd3S10 exhibits a high second-harmonic-generation intensity (1.8 times that of AgGaS2) and a significantly higher laser-induced damage threshold (14.3 times that of AgGaS2), which is the first case possessing an infrared (IR) nonlinear optical (NLO) property in the quaternary AE/RE/TM/Q (AE = alkaline-earth metals; RE = rare-earth metals; TM = d-block transition metals; and Q = chalcogen) systems. Moreover, theoretical investigations of the structure–property relationship indicate that the combined action of various types of NLO-active units makes the main contribution to the SHG activity. This discovery may shed light on broadening the frontiers of IR-NLO materials.