修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

393 条数据
?? 中文(中国)
  • A Novel Chemiluminescent Probe Based on 1,2-Dioxetane Scaffold for Imaging Cysteine in Living Mice

    摘要: A novel chemiluminescent probe for detection of cysteine (Cys) from other biothiols has been reported by utilizing the excellent chemiluminescent Schaap’s adamantylidene-dioxetane scaffold. After careful assessment, the probe CL-Cys could detect Cys with high sensitivity and total light photons increased with 28-fold after the probe was treated with Cys, with the detection limit of 7.5 x 10-8 M. Finally, CL-Cys was further utilized to the chemiluminescent imaging of endogenous Cys in living mouse. In general, this probe has a remarkable ability of detecting Cys, which provides a valuable method for interrogation the Cys roles in more biological and pathological processes.

    关键词: Chemiluminescent probe,1,Cysteine,2-dioxetane,Chemiluminescent imaging,In vivo imaging.,Living animal

    更新于2025-09-23 15:23:52

  • Peptide-based ratiometric fluorescent probe for highly selective detection of Cd (II) and its application in bioimaging

    摘要: This work reported a new peptide fluorescent probe L including dansyl group (acceptor) and tryptophan (donor) via imitated the binding sites of natural protein. L exhibited exclusively selective ratiometric fluorescence response towards Cd2+ ions over other metal ions based on fluorescent resonance energy transfer (FRET) effects. As designed, L showed exciting sensitivity to Cd2+ ions in aqueous media, and the detection limits are less than 27.5 nM. In addition, the binding pattern of L and Cd2+ was confirmed by fluorescence titration analysis which was found to be 2:1 and further it was confirmed by Job's plot. What' more, L exhibited very low biotoxicity and exciting cell infiltration, and have been successfully used for fluorescence imaging of Cd2+ ions in living HeLa cells.

    关键词: Cell imaging,Fluorescent probe,Peptide,Cadmium ion,Ratiometric

    更新于2025-09-23 15:23:52

  • Current-induced domain wall oscillations in a nanowire imaged by time-resolved photoemission electron microscopy

    摘要: We study reversible domain wall motion in half-ring Ni80Fe20 nanowires on a nanosecond (ns) timescale in a truly current-induced pump-probe experiment using an energy filtered, aberration-corrected photoemission electron microscope. The x-ray magnetic circular dichroism signal is probed at different time delays before, during and after the current pulse in a stroboscopic mode with circularly polarized synchrotron radiation in the energy range of the Fe L3-edge (707 eV). We observe lateral domain wall oscillations with a frequency of ~ 0.4 GHz. Comparing the results to a proposed string model, we find that the domain wall oscillations can be described as string-like asymmetric oscillations.

    关键词: Synchrotron radiation,Photoemission electron microscopy,X-ray magnetic circular dichroism,Pump-probe mode

    更新于2025-09-23 15:23:52

  • Investigation of ultrafast energy transfer mechanism in BODIPY–Porphyrin dyad system

    摘要: Novel β-fused BODIPY-Porphyrin compounds that contain free base porphyrin (TPP2BDP) and its Ni(II) complex (NiTPP2BDP) were synthesized to investigate intramolecular energy transfer mechanisms of β-fused BODIPY-porphyrin dyads and effect of the unfilled d shell metal ion on energy transfer mechanism. Fluorescence spectra of compounds exhibited that BODIPY emission was diminished upon excitation of the BODIPY unit because of the energy transfer from BODIPY to porphyrin unit. Femtosecond pump-probe spectroscopy measurements revealed that energy transfer of investigated compounds are faster than previous studies in literature. Rapid energy transfer (about 500 fs) from BODIPY to porphyrin was observed for both compounds when BODIPY unit is excited due to direct linkage of BODIPY to porphyrin unit. Intersystem crossing mechanism was also observed for the compound that contains free base porphyrin (TPP2BDP), whereas d-d transition was observed for the compound that contains metalloporphyrin (NiTPP2BDP) due to unfilled d orbital of Ni(II) ion.

    关键词: Fast energy transfer,Borondipyrromethene,Porphyrin,Ultrafast pump-probe spectroscopy

    更新于2025-09-23 15:23:52

  • Preparation of fluorescent in situ hybridisation probes without the need for optimisation of fragmentation

    摘要: DNA-fluorescence in situ hybridisation (DNA-FISH) allows visualisation of chromosome organisation and fluorescently labelled DNA fragments that are often produced from rearrangement. FISH probes are pools of short template plasmids that contain large genomic inserts. For effective sample penetration and target hybridisation it is critical that probe fragments are between 200 and 500bp. Production of these short probes requires significant optimisation and can be confounded access to expensive sonication equipment or inherent sequence features that influence enzymatic fragmentation or amplification. Here we demonstrate that effective FISH probes can be prepared without the need for optimisation of fragmentation using a cocktail of two the 4bp recognition sequence restriction enzymes CviQI and AluI.

    关键词: Cancer,Fluorescence in situ hybridization,Translocation,FISH,Probe

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM) - Nagoya (2018.8.29-2018.8.31)] 2018 IEEE International Workshop on Electromagnetics:Applications and Student Innovation Competition (iWEM) - Kanji Patch Antennas

    摘要: This article introduces the basic concepts of Kanji patch antennas. We use two novel L-probe-fed Guo- and Meng-shaped patches operating in circular polarization as examples. The main parameters of these symmetrical and asymmetrical shaped patch antennas were studied and optimized via computer-aided simulation.

    关键词: Kanji patch antennas,circular polarization,L-shaped feeding probe,artistic antenna

    更新于2025-09-23 15:23:52

  • Facile method for iodide ion detection via the fluorescence decrease of dihydrolipoic acid/beta-cyclodextrin protected Ag nanoclusters

    摘要: In this work, novel photoluminescent Ag nanoclusters (Ag NCs) with red emission are synthesized and successfully used for detecting iodide ion (I?). The dihydrolipoic acid (DHLA) is used as the stabilizing agent and beta-cyclodextrin (β-CD) is used as the auxiliary stabilizing agent. DHLA and β-CD are combined with Ag atoms by the formation of Ag-S bonds and hydrophobic interaction, respectively. Functionalization of β-CD endows good photoluminescent properties and solubility in water to the Ag NCs. The obtained DHLA and β-CD-protected Ag NCs (DHLA/β-CD-Ag NCs) are spherical and display a dispersed state. However, the DHLA/β-CD-Ag NCs are aggregated in the presence of I?, accompanied by the decrease in their fluorescence intensity. Because the integrity of β-CD cavities is retained on the surface of DHLA/β-CD-Ag NCs, which preserves their capability for I? host–guest recognition, the DHLA/β-CD-Ag NCs combine with I? through the formation of inclusion complexes. Based on this phenomenon, the prepared DHLA/β-CD-Ag NCs can be designed as a novel fluorescent probe for I? detection. The limit of detection (LOD) is calculated as 0.06 μM, indicating that it is an ideal probe for I? detection in practical applications.

    关键词: Ag nanoclusters,Fluorescent probe,Beta-cyclodextrin,Dihydrolipoic acid,Iodide ion

    更新于2025-09-23 15:23:52

  • Ultrasensitive U-shaped fiber optic LSPR cytosensing for label-free and in situ evaluation of cell surface N-glycan expression

    摘要: Label-free and in situ detection of N-glycan expression on surface of cells is vital for understanding the progression of cancer. Herein, cytosensing based on U-shaped fiber optic local surface plasmon resonance (LSPR) was developed for cancer cell detection and N-glycan evaluation on cell surface. The U-shaped fiber optic LSPR has high refractive index sensitivity (RIS). Therefore, U-shaped fiber optic LSPR cytosensing afforded ultrasensitivity for cancer cell detection with the limit of detection (LOD) of 30 cells/mL and good linearity in a wide range of 1×102-1×106 cells/mL under the optimal conditions of modified AuNPs size and Con A concentration. The U-shaped fiber optic LSPR cytosensing shows more than 29 times lower limit of detection than the straight ones. More importantly, the prepared U-shaped cytosensing was applied to evaluate the N-glycan expression level on the surface of cancer cells under different concentration external stimuli of inhibitor tunicamycin (TM). Noticeably, U-shaped fiber optic LSPR cytosensing showed an acceptable reproducibility, satisfactory anti-interference and good selectivity, and was also applied in the assessment of N-glycan expression on surface of six kinds of cell lines. Therefore, the U-shaped fiber optic LSPR offers a feasible tool in biophysical research and clinical diagnosis for cancer.

    关键词: Cancer cell,N-Glycan expression,Cytosensing,U-shaped fiber optic probe,Local surface plasmon resonance

    更新于2025-09-23 15:23:52

  • A coumarin-based colorimetric fluorescent probe for rapid response and highly sensitive detection of hydrogen sulfide in living cells

    摘要: Hydrogen sulfide (H2S) plays a vital role in numerous biological processes in living organisms. To better understand its functions, a fluorescent probe to fast and sensitively detect H2S is imminently needed. Keep this in mind, we reasonably designed probe DHC for detecting H2S based on α, β-unsaturated ethanoylcoumarin fluorophore. The limit of detection (LOD) is found to be as low as 5 × 10?8 M, which is superior to most reported fluorescent probes to detect H2S. Furthermore, the wide pH range of 4–11 makes it capable of application in biological systems. Most importantly, MTT assays and cell imaging experiments indicate that probe DHC has hypotoxicity and outstanding membrane permeability, which makes DHC successful imaging of H2S in Baby Hamster Syrian Kidney (BHK) cells.

    关键词: Cell-imaging,Fluorescent probe,Rapid response,H2S,Coumarin

    更新于2025-09-23 15:23:52

  • Fluorescent Ag clusters conjugated with anterior gradient-2 antigen aptamer for specific detection of cancer cells

    摘要: Fluorescent probes with small size, low toxic and specific recognition are of fundamental interests as well as of practical prospects in bioimaging. Though various probes have been reported up to now, including traditional organic dye, quantum dots, rare earth-based particles, and recently emerged carbon dots, silicon dots, polymer dots and metal cluster et al., the relatively large size and lack of specify are far from satisfaction in cellular imaging. As confirmed in previous reports, the large size might influence the functions of target, where the consequent drawback of non-specific is requiring conjugate with additional ligands which brings even larger size and complex procedures. In such a context, fluorescent metal nanoclusters have rapidly attracted widely concern for their integrated advantages of small size, high stability, unique selectivity and tunable properties by simply selecting different stabilizer. In considering a wide variety of stabilizer, aptamer, as a class of ssDNA, has received particular interest because of the easy production, reduced size comparing with antibody and selectively binding ability in molecule level with specific structures. Former researches have proved that cytosine has strong interaction with Ag cations. Therefore, colorful Ag clusters (AgNCs) have been continuously prepared using different DNA sequences in a simple reductive reaction after mixing both aptamer and Ag cation. Additionally, the as synthesized AgNCs do not influence the selectivity of the aptamer itself. For example, Sun et al. reported a one-step process to synthesize silver nanoclusters by specific aptamer which can selectively image the nuclei of CCRF cells, clearly demonstrates the strength of the aptamer capsulated Ag clusters. Anterior gradient protein 2 homolog (AGR), a homolog of xenopus anterior gradient-2 (XAG-2) of Xenopus laevis, is a typical protein that secret by gland cancer cell. Since being discovered as a pro-oncogenic protein that weakens p53 gene activity in 2004. Clinical studies have shown that AGR is highly expressed in pancreatic, breast, and prostate cancer cells, etc. The molecular function and clinical relevance of AGR with variety cancers have thus been increasingly investigated. Specifically, it is a functional protein that plays a key role in variety of biological systems, including the development of vertebrate tissue and the inflammatory tissue injury response. Overall, Tian's results demonstrated that AGR overexpression could predict poor overall survival (OS) and poor time to tumor progression (TTP) of all solid tumor patients. Therefore, fluorescence recognizing of AGR is important for detecting gland cancer cells. At present, a number of reports related with AGR have been reported, but few on specific recognition probes. Through a series of screening, Wu et al. discovered AGR's corresponding aptamer “C14B1”. Few years later, Hu et al. successfully achieved the direct detection of AGR in vitro. However, in the cell imaging field, there is scarcely report on AGR detection. Therefore, synthesis of fluorescent AgNCs conjugating with aptamer to target AGR could provide a novel method for recognizing human gland cancer cell with a high selectivity, efficiency, and low cytotoxicity. In this paper, modified AGR aptamer (MA) were used as template to synthesize AgNCs. Specifically, MA's sequence is 5′-CGG GTG GGA GTT GTG GGG GGG GGT GGG AGG GTT TTTTT CCC CCC CCC CCC-3′ (50 bases). This sequence consists of two functional parts, AGR-apt sequence for recognition AGR in breast cancer (MCF-7) cells, where 12 cytosine base sequence (12C) for effectively preparing fluorescent AgNCs. According to Li's research, a T5 loop (-TTTTT-) could enhance the fluorescence intensity and avoid the influence of space hindrance. It was incorporated between the 3′ end of the apt and 12C sequence. Eventually, according to optimized reaction conditions, MA stabilized silver nanocluster (MA@AgNCs) with a small size, suitable stability, good selectivity was prepared. The fluorescence excitation peak and emission peak of MA@AgNCs were located at 510 nm and 565 nm respectively with a quantum yield as high as 87.43%. Moreover, MA@AgNCs shows descent specific recognition of MCF-7 cells, suggesting the prepared MA@AgNCs have the ability to selective target gland cancer cell and potentially utilized for clinical diagnosis and treatment.

    关键词: Bio-probe,Cell imaging,Anterior gradient-2 antigen,Silver nanoclusters,Aptamer

    更新于2025-09-23 15:23:52