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Latex Microspheres (latex + microsphere)
Selected AbstractsEnhancement of Förster Energy Transfer within a Microspherical CavityCHEMPHYSCHEM, Issue 11 2005Hideki Fujiwara Dr. Abstract Energy transfer from pyrene to perylene molecules co-doped within a poly(methyl methacrylate) latex microsphere was drastically accelerated relative to free space. Fluorescence spectra of the microspheres showed that the relative emission intensities of pyrene and perylene changed with the sphere diameter. Analyses of emission decay profiles clarified that Förster-type energy-transfer processes were induced and that the transfer rates increased within the microspherical cavity. This enhancement can be ascribed not only to the quantum electrodynamic effects on the pyrene emission rate, but also the cavity effect of increasing the overlapping factor between donor emission and acceptor absorption spectra. [source] High-sensitivity detection of oxytetracycline using light scattering agglutination assay with aptasensorELECTROPHORESIS, Issue 18 2010Keesung Kim Abstract We present an aptamer-based biosensor (aptasensor) for rapid and high-sensitive detection of oxytetracycline (OTC) antibiotic in PBS inside a Y-channel PDMS microfluidic device. The detection was made by real-time monitoring of the agglutination assay of ssDNA aptamer-conjugated polystyrene latex microspheres with proximity optical fibers. The agglutination assay was performed with serially diluted OTC antibiotic solutions using highly carboxylated polystyrene particles of 920,nm diameter conjugated with OTC-binding ssDNA aptamer. Proximity optical fibers were used to measure the increase in 45° forward light scattering of the aggregated particles by fixing them around the viewing cell of the device with stable angle and distance to the detector. The detection limit was around 100,ppb for the current aptasensor system with the detection time less than 3,min. [source] Noxious Somatic Inputs to Hypothalamic-Midbrain Projection Neurones: a Comparison of the Columnar Organisation of Somatic and Visceral Inputs to the Periaqueductal Grey in the RatEXPERIMENTAL PHYSIOLOGY, Issue 2 2002D. M. Parry The induction of Fos protein was used to localise hypothalamic neurones activated by noxious somatic stimulation. This was combined with retrograde transport of fluorescent latex microspheres from identified ,pressor' and ,depressor' sites in the dorsolateral/lateral or ventrolateral columns of the periaqueductal grey (PAG). Fos-positive neurones were found throughout the rostral hypothalamus. Of those neurones activated by noxious somatic stimuli that projected to the PAG all but one was retrogradely labelled from sites that included the lateral column. Only one neurone was double labelled following injection of tracer at a depressor site in the ventrolateral PAG. This is in marked contrast to visceroresponsive hypothalamic neurones, a larger proportion of which project to the PAG and which, as reported previously, preferentially target depressor sites in the ventrolateral sector. These results are discussed in relation to the roles of the anterior hypothalamus and the different functional columns of the PAG in co-ordinating autonomic and sensory functions in response to nociceptive inputs originating in different peripheral domains. [source] Intracellular fibroblast growth factor produces effects different from those of extracellular application on development of avian cochleovestibular ganglion cells in vitroJOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2003Masako M. Bilak Abstract In an avian coculture system, the neuronal precursors of the cochleovestibular ganglion typically migrated from the otocyst and differentiated in response to soluble fibroblast growth factor (FGF-2), which had free access to FGF receptors on the cell surface. Free FGF-2 switched cells from a proliferation mode to migration, accompanied by increases in process outgrowth, fasciculation, and polysialic acid expression. Microsphere-bound FGF-2 had some of the same effects, but in addition it increased proliferation and decreased fasciculation and polysialic acid. As shown by immunohistochemistry, FGF-2 that was bound to latex microspheres depleted the FGF surface receptor protein, which localized with the microspheres in the cytoplasm and nucleus. For microsphere-bound FGF-2, the surface receptor-mediated responses to FGF-2 appear to be limited and the door opened to another venue of intracellular events or an intracrine mechanism. © 2003 Wiley-Liss, Inc. [source] | ||||||||||