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Luminescence color change of poly-(2,5-dioctyl para-phenyleneethynylene) through variations of excitation intensity was reported. The two ways of changing the emission color are possible and para-pheyleneethynylene is expected to be useful in color tuning applications.

The identification of a multicolor set of water-soluble oligodeoxyfluoroside (ODF) dyes that exhibit emission colors across the visible spectrum and all of which can be simultaneously excited by long-wavelength ultraviolet (UV) light is described. The results have shown that ODF dyes are useful as labels in biological systems, which has allowed the simultaneous tracking of multiple species by color and the visualization in moving systems where classical fluorophores have failed.

Oligomeric DNA-scaffolded fluorophores are efficiently quenched by methyl viologen and other known quenchers. The quenching efficiency has increased with increasing oligomer length and the efficient quenching can occur with oligomers of varied hydrocarbon fluorophores that exhibit excimer/exciplex excited-state emissions.

The dramatic blue and/or red shifts of emission and adsorption upon coordination of metal cations to cruciforms are demonstrated. The optical properties of the cruciforms change via switching of the intramolecular charge-transfer band depending upon the binding preference of the metal.

The arrays of self-assembled picoliter holes1-7 fabricated from poly (para-henyleneethynylene) (PPE, 4) are described. The thermal cross-linking of these arrays, leads to their collapse under formation of self-assembled picoliter hole array with a density of approximately 40000 holes per mm2.

The gold nanorods, surface-functionalized with biotin, can be assembled prefentially in an end-to-end fashion upon the addition of a streptavidin linker is reported. These results provide evidence that the chemical reactivity of nanomaterials is shape-dependent and may be useful in construction of future nanoscale assemblies.

The amorphous poly[p-bis-(3,7-dimethyloctyl)phenyleneethynylene] is investigated in which all of the PE units are chirally substituted. It is concluded that the prominent peaks in the circular dichroism (CD) and circularly polarized photoluminescence (CPPL) spectra have the same physical origin, which most likely is not an interchain exicton coupling.

An acetylene dye rotaxane with alpha-cyclodextrin and its free dye (FD) analogue is synthesized using a Heck-Cassar-Sonogasgira-Hagihara-type reaction. The FD with four carboxylic acids is highly sensitive to various metal ions, showing high Stern-Volmer constants, [K.sub.SV] and there is no significant difference in the electronic absorption and emission spectra of free and rotaxanated dyes.

Perivascular adipose tissue (PVAT) reduces vasoconstriction to norepinephrine (NE). A mechanism by which PVAT could function to reduce vascular contraction is by decreasing the amount of NE to which the vessel is exposed. PVATs from male Sprague-Dawley rats were used to test the hypothesis that PVAT has a NE uptake mechanism. NE was detected by HPLC in mesenteric PVAT and isolated adipocytes. Uptake of NE (10 μM) in mesenteric PVAT was reduced by the NE transporter (NET) inhibitor nisoxetine (1 μM, 73.68 ± 7.62%, all values reported as percentages of vehicle), the 5-hydroxytryptamine transporter (SERT) inhibitor citalopram (100 nM) with the organic cation transporter 3 (OCT3) inhibitor corticosterone (100 μM, 56.18 ± 5.21%), and the NET inhibitor desipramine (10 μM) with corticosterone (100 μM, 61.18 ± 6.82%). Aortic PVAT NE uptake was reduced by corticosterone (100 μM, 53.01 ± 10.96%). Confocal imaging of mesenteric PVAT stained with 4-[4-(dimethylamino)-styrl]-N-methylpyridinium iodide (ASP+), a fluorescent substrate of cationic transporters, detected ASP+ uptake into adipocytes. ASP+ (2 μM) uptake was reduced by citalopram (100 nM, 66.68 ± 6.43%), corticosterone (100 μM, 43.49 ± 10.17%), nisoxetine (100 nM, 84.12 ± 4.24%), citalopram with corticosterone (100 nM and 100 μM, respectively, 35.75 ± 4.21%), and desipramine with corticosterone (10 and 100 μM, respectively, 50.47 ± 5.78%). NET protein was not detected in mesenteric PVAT adipocytes. Expression of Slc22a3 (OCT3 gene) mRNA and protein in PVAT adipocytes was detected by RT-PCR and immunocytochemistry, respectively. These end points support the presence of a transporter-mediated NE uptake system within PVAT with a potential mediator being OCT3. [ABSTRACT FROM AUTHOR]

In this study, we report the efficient identification of proteins using (6-hydroxy-2-naphthyl)ethenyl pyridinium dyes ( HNEPs). These dyes exhibited characteristic fluorescence responses, showing enhanced fluorescence with a red shift in the case of bovine serum albumin. The nature of the interaction between the dye and the protein was examined using a combination of various spectroscopic techniques. A time-dependent density functional theory analysis supported the strong environment-dependent fluorescence emission properties of the dyes. The current investigation clearly demonstrates that a selective optical response HNEPs can find potential usefulness as bio-sensing probes. [ABSTRACT FROM AUTHOR]

On the basis of the highly stable G2H (2 : 1) ternary complex formed by two methyl viologen cation radicals inside the cavity of cucurbit[8]uril, we prepared three monocationic 4-phenylpyridinium derivatives: 1-(hydroxyethyl)-4-phenyl-pyridinium ( 1+) bromide, 1-(octaethyleneglycol)-4-phenyl-pyridinium ( 2+) chloride, and 4-[4-(methoxymethoxy)phenyl]pyridinium ( 3+) iodide, as possible guests for 2 : 1 complexation inside cucurbit[8]uril. We also investigated a fourth monocationic guest ( 4+), in which a central vinylidene group is inserted to elongate the 4-phenyl-pyridinium residue. Using 1H NMR and UV-Vis spectroscopic data and mass spectrometric data, we obtained unequivocal evidence for the formation of G2H (2 : 1) ternary complexes in all cases. The stoichiometry of the complexes was further verified by continuous variation (Job) plots, and in some cases, high resolution ESI-MS spectrometric data. Diffusion coefficient measurements, using 1H NMR pulse gradient spin echo techniques, yielded values consistent with the formation and expected structures of the ternary complexes. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]