In the work discussed in this paper, the effect of a high surface-to-volume ratio of a microfluidic detection cell on fluorescence quenching was studied. It was found that modification of the geometry of a microchannel can provide a wider linear range. This is a phenomenon which should be taken into consideration when microfluidic systems with fluorescence detection are developed. The dependenc...

Inverted membrane vesicles from strain 7, a wild type Escherichia coli K12 strain, actively transport calcium with energy supplied either by respiration or by ATP. These vesicles also have energy-linked quenching of quinacrine fluorescence. Membranes of strain 7, depleted of Mg2+ATPase by EDTA treatment, lack both activities. Membrane vesicles from strain NR70, a mutant lacking the Mg2+ATPase, ...

Quenching of a fluorophore is significantly influenced by the molecular structure of the quencher. In this study, photoluminescence quenching by nitroaromatic compounds was evaluated to assess the molecular interaction between nitroaromatic molecules and the photoluminescent tyrosyl bolaamphiphile self-assembly, a nanoscale optical photoluminescent probe. Both the aromatic structure and hydroph...

We have analyzed the decays of the fluorescence of colloidal CdSe quantum dots (QDs) suspensions during dilution and titration by the ligands. A ligand shell made of a combination of trioctylphosphine (TOP), oleylamine (OA) and stearic acid (SA) stabilizes the as-synthesized QDs. The composition of the shell was analyzed and quantified using high resolution liquid state 1H nuclear magnetic reso...

In the present work the effect of different concentration of halide quenchers (Cl, Br, I) on 4-methyl-5-ethoxy-7-methoxy coumarin (1) and 4-methyl-5,7-diethoxy coumarin (2) in aqueous solutions have been carried out at 20 temperature. It was observed that the fluorescence intensity of these coumarin derivatives decrease with increase in the concentration of the quenchers except Cl quencher. Fur...

Recently, enzymatic quorum quenching has proven its potential as an innovative approach for biofouling control in the membrane bioreactor (MBR) for advanced wastewater treatment. However, practical issues on the cost and stability of enzymes are yet to be solved, which requires more effective quorum quenching methods. In this study, a novel quorum quenching strategy, interspecies quorum quenchi...

Quenching cooling rate of rotary hollow cylinder by one row of water impinging jets has been experimentally studied. Water jets (d = 8 mm) with sub-cooling 55 to 85 ◦C and Reynolds number 8,006 to 36,738 impinged over rotary hot hollow cylinder (rotation speed 10 to 70 rpm) with initial temperature 250 to 600 ◦C. Impingement impact angle of row of jets varied between 0 to 135 ◦ and jet-to-jet s...

Recently, a very interesting observation relating energy generation to the quenching of the fluorescence of the uncoupler atebrin in isolated chloroplasts has been described by Kraayenhof [ 11. It was shown that the required energy could be provided by electron transport, ATP hydrolysis or a pH gradient, and it was therefore suggested that the extent of quenching may be used to measure the ‘ene...

bacteria use a chemical language to communicate with each other which enables them to synchronize gene expression as a result of cell density. this special language which is called quorum sensing (qs) is based on producing and sensing the small signals and eventually leads them to perceive when a minimum population unit is reached. on the contrary, quorum sensing blockade (quorum quenching) has...

An alkaline phosphatase activity detection system was constructed based on the different quenching effect of the enzyme substrate and product on the β-CD-functionalized CdTe QDs.