1,4-Diazobicyclo(2,2,2)octane-modified multi-ammonium derivatives as ratiometric fluorescent sensors for lipopolysaccharide
摘要:
A series of pyrene derivatives bearing multi-quaternary ammonium 1,4-diazobicyclo(2,2,2)octane groups were synthesised as ratiometric fluorescent sensors for lipopolysaccharide (LPS) in aqueous solution. Ratiometric changes in fluorescence spectra of the sensors were observed from the pyrene monomerexcimer conversion which is modulated by the supramolecular self-assembly between sensors and LPS. These sensors show high selectivity towards LPS with the detection limit down to tens of nanomolar levels. The interaction mechanism between the sensors and LPS was also discussed.
1,4-Diazobicyclo(2,2,2)octane-modified multi-ammonium derivatives as ratiometric fluorescent sensors for lipopolysaccharide
摘要:
A series of pyrene derivatives bearing multi-quaternary ammonium 1,4-diazobicyclo(2,2,2)octane groups were synthesised as ratiometric fluorescent sensors for lipopolysaccharide (LPS) in aqueous solution. Ratiometric changes in fluorescence spectra of the sensors were observed from the pyrene monomerexcimer conversion which is modulated by the supramolecular self-assembly between sensors and LPS. These sensors show high selectivity towards LPS with the detection limit down to tens of nanomolar levels. The interaction mechanism between the sensors and LPS was also discussed.
A new polyhedral oligomeric silsesquioxane (POSS) core star-like supramolecular blue-light electroluminescent material, 4-uracilbutyl-1-methylpyrene ether (U-PY)/octakis[dimethyl(N-(6-acetamidopyridin-2 yl))siloxy] silsesquioxane (ODAP-POSS) has been synthesized. This U-PY/ODAP-POSS contains eight pyrene chromophore arms formed through complementary uracil-diamidopyridine (U-DAP) pairs and exhibits high quantum efficiencies and good solution processing properties. The photoluminescence spectra of U-PY/ODAP-POSS (50/50) reveal that the color is stable after heating the sample at 150 °C for 1 h, in contrast, the pyrene/ODAP-POSS (50/50) shows significant thermal quenching. An electroluminescence (EL) device based on U-PY/ODAP-POSS exhibits higher maximum brightness and higher luminance efficiency relative to that of the U-PY. In addition, U-PY/ODAP-POSS also behaves as an effective dopant that enhances energy transfer from itself to MEH-PPV. The U-PY/ODAP-POSS-doped MEH-PPV blends exhibit high luminance efficiency, 1.45 times greater than MEH-PPV.
C–H alkylations of purine nucleosides were achieved by means of user-friendly nickelcatalysis with ample substrate scope and high levels of chemo, site and regio control, which among others enabled the direct fluorescent labeling of purines in terms of late stage diversification.
The association constant between guanine and a series of cytosine derivatives in dichloromethane was determined by fluorescence quenching experiment of pyrene connected to guanine with methylene spacer. The association constant for guanine with 5-methyl-cytosine is found to be higher than that with cytosine. This enables us to distinguish target cytosine from its derivatives. (c) 2005 Elsevier B.V. All rights reserved.
1,4-Diazobicyclo(2,2,2)octane-modified multi-ammonium derivatives as ratiometric fluorescent sensors for lipopolysaccharide
作者:Wenwen Zhao、Jiasheng Wu、Weimin Liu、Pengfei Wang
DOI:10.1080/10610278.2012.732224
日期:2013.2
A series of pyrene derivatives bearing multi-quaternary ammonium 1,4-diazobicyclo(2,2,2)octane groups were synthesised as ratiometric fluorescent sensors for lipopolysaccharide (LPS) in aqueous solution. Ratiometric changes in fluorescence spectra of the sensors were observed from the pyrene monomerexcimer conversion which is modulated by the supramolecular self-assembly between sensors and LPS. These sensors show high selectivity towards LPS with the detection limit down to tens of nanomolar levels. The interaction mechanism between the sensors and LPS was also discussed.