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High Fluorescence (high + fluorescence)

Distribution by Scientific Domains
Polymers and Materials Science40%
Life Sciences40%

Terms modified by High Fluorescence

  • high fluorescence quantum yield
    		•

    Selected Abstracts

    Generic Strategy of Preparing Fluorescent Conjugated-Polymer-Loaded Poly(DL -lactide- co -Glycolide) Nanoparticles for Targeted Cell Imaging

    ADVANCED FUNCTIONAL MATERIALS, Issue 22 2009
    Kai Li
    Abstract A general strategy for the preparation of highly fluorescent poly(DL-lactide- co -glycolide) (PLGA) nanoparticles (NPs) loaded with conjugated polymers (CPs) is reported. The process involves encapsulation of organic-soluble CPs with PLGA using a modified solvent extraction/evaporation technique. The obtained NPs are stable in aqueous media with biocompatible and functionalizable surfaces. In addition, fluorescent properties of the CP-loaded PLGA NPs (CPL NPs) could be fine-tuned by loading different types of CPs into the PLGA matrix. Four types of CPL NPs are prepared with a volume-average hydrodynamic diameter ranging from 243 to 272,nm. The application of CPL NPs for bio-imaging is demonstrated through incubation with MCF-7 breast cancer cells. Confocal laser scanning microscopy studies reveal that the CPL NPs are internalized in cytoplasm around the nuclei with intense fluorescence. After conjugation with folic acid, cellular uptake of the surface-functionalized CPL NPs is greatly enhanced via receptor-mediated endocytosis by MCF-7 breast cancer cells, as compared to that for NIH/3T3 fibroblast cells, which indicates a selective targeting effect of the folate-functionalized CPL NPs in cellular imaging. The merits of CPL NPs, such as low cytotoxicity, high fluorescence, good photostability, and feasible surface functionalization, will inspire extensive study of CPL NPs as a new generation of probes for specific biological imaging and detection. [source]

    Photonic Shell-Crosslinked Nanoparticle Probes for Optical Imaging and Monitoring

    ADVANCED MATERIALS, Issue 13 2009
    Nam S. Lee
    A pH-insensitive fluorophore is fabricated to give pH-driven responses through its covalent incorporation within a nanostructure derived from pH-responsive polymers. Fluorophore shell-crosslinked nanoparticles (SCKs) demonstrate notable enhancement of photophysical properties in the physiological pH region. Fluorophore SCKs are designed to swell at higher pH values and shrink as the pH is lowered, producing high fluorescence versus low fluorescence outputs, respectively. [source]

    Amino terminal interaction in the prion protein identified using fusion to green fluorescent protein

    JOURNAL OF NEUROCHEMISTRY, Issue 5 2003
    Yongxiu Yao
    Abstract In contrast to the well-characterized carboxyl domain, the amino terminal half of the mature cellular prion protein has no defined structure. Here, following fusion of mouse prion protein fragments to green fluorescence protein as a reporter of protein stability, we report extreme variability in fluorescence level that is dependent on the prion fragment expressed. In particular, exposure of the extreme amino terminus in the context of a truncated prion protein molecule led to rapid degradation, whereas the loss of only six amino terminal residues rescued high level fluorescence. Study of the precise endpoints and residue identity associated with high fluorescence suggested a domain within the amino terminal half of the molecule defined by a long-range intramolecular interaction between 23KKRPKP28 and 143DWED146 and dependent upon the anti-parallel ,-sheet ending at residue 169 and normally associated with the structurally defined carboxyl terminal domain. This previously unreported interaction may be significant for understanding prion bioactivity and for structural studies aimed at the complete prion structure. [source]

    Bronze Age painted plaster in Mycenaean Greece: a pilot study on the testing and application of micro-Raman spectroscopy

    JOURNAL OF RAMAN SPECTROSCOPY, Issue 8-9 2004
    Ann Brysbaert
    Abstract Since the first discoveries of Minoan and Mycenaean painted plaster around the end of the 19th and early 20th centuries, iconographic and, to a lesser extent, technological studies have gone hand in hand in order to understand how these prehistoric societies were able to produce some of the earliest and most significant works of art in Bronze Age Europe and the eastern Mediterranean. These paintings claim to be among the first to be executed in the buon fresco technique. Past technological studies employed wet chemical methods, x-ray diffraction (XRD), optical emission spectroscopy and a range of microscopic techniques based on cross-sections of samples in order to investigate these fragmentary paintings. Most of these methods required destructive sampling and this is now, rightly so, very much restricted. Consequently, other non-micro-destructive approaches are being tested at present. Micro-Raman spectroscopy (MRS) has proven more than once its potential for non-destructive analysis of works of art and in archaeology in the recent past. Its application to this early fragmentary material is presented here for the first time. Interesting results were the identification of both organic (indigo) and non-crystalline materials (limonite), which complements the knowledge obtained from traditionally used techniques. Although not without problems (high fluorescence prevented identification of Egyptian Blue), non-destructive MRS yielded results comparable to XRD and provided the first identification of indigo blue on this medium, and can hence be considered very useful in future sample-reducing strategies considering these scarce materials. Copyright © 2004 John Wiley & Sons, Ltd. [source]

    Effect of polyethylene glycol on the thermal stability of green fluorescent protein

    BIOTECHNOLOGY PROGRESS, Issue 1 2010
    Letícia C. de Lencastre Novaes
    Abstract Green fluorescent protein (GFP) shows remarkable structural stability and high fluorescence; its stability can be directly related to its fluorescence output, among other characteristics. GFP is stable under increasing temperatures, and its thermal denaturation is highly reproducible. Some polymers, such as polyethylene glycol, are often used as modifiers of characteristics of biological macromolecules, to improve the biochemical activity and stability of proteins or drug bioavailability. The aim of this study was to evaluate the thermal stability of GFP in the presence of different PEG molar weights at several concentrations and exposed to constant temperatures, in a range of 70,95°C. Thermal stability was expressed in decimal reduction time. It was observed that the D -values obtained were almost constant for temperatures of 85, 90, and 95°C, despite the PEG concentration or molar weight studied. Even though PEG can stabilize proteins, only at 75°C, PEG 600 and 4,000 g/mol stabilized GFP. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source]