Advertisement
Advertise here Publish your press releases here Sponsor BioPortfolio
Follow us on Twitter Sign up for daily news and research emails Contributors wanted

A first principles study of fluorescence quenching in rhodamine B dimers: how can quenching occur in dimeric species?

18:27 EDT 16th April 2014 | BioPortfolio

Summary of "A first principles study of fluorescence quenching in rhodamine B dimers: how can quenching occur in dimeric species?"

Rhodamine B (RhB) is widely used in chemistry and biology due to its high fluorescence quantum yield. In high concentrations, the quantum yield of fluorescence decreases considerably which is attributed to the formation of RhB dimers. In the present work, a possible mechanism of fluorescence quenching in RhB dimers is investigated with the use of time-dependent density functional theory (TD-DFT). The excited states of monomeric and dimeric RhB species have been studied both in the gas phase and in solution with the use of the TD-BLYP/6-311G* method. Results of the calculations suggest that quenching can occur via an internal conversion to the charge-transfer singlet excited states, which can be followed by an intersystem crossing with the charge-transfer triplet states. A possibility to reduce the loss of the fluorescence quantum yield is discussed.

Affiliation

Theoretical Chemistry, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen, Nijenborgh 4, Groningen 9747AG, The Netherlands.

Journal Details

This article was published in the following journal.

Name: Physical chemistry chemical physics : PCCP
ISSN: 1463-9084
Pages: 11238-44

Links

PubMed Articles [15264 Associated PubMed Articles listed on BioPortfolio]

The relationship between non-photochemical quenching of chlorophyll fluorescence and the rate of photosystem 2 photochemistry in leaves.

It has been suggested previously that non-photochemical quenching of chlorophyll fluorescence is associated with a decrease in the rate of photosystem 2 (PS 2) photochemistry. In this study analyses o...

The effect of high-energy-state excitation quenching on maximum and dark level chlorophyll fluorescence yield.

The quenching of variable fluorescence yield (qN) and the quenching of dark level fluorescence yield (q0) directly atributable to high-energy-state fluorescence quenching (qE) was studied to distingui...

Non-photochemical quenching of Fo in leaves is emission wavelength dependent: consequences for quenching analysis and its interpretation.

The effects of light-induced non-photochemical quenching on the minimal Fo, and variable Fv, fluorescence emissions at 690 and 730 nm in leaves were determined. Non-photochemical quenching of Fo, but...

Energy-dependent quenching of dark-level chlorophyll fluorescence in intact leaves.

A new type of modulation fluorometer was used in the study of energy-dependent chlorophyll fluorescence quenching (qE) in intact leaves. Under conditions of strong energization of the thylakoid membra...

Induction of photochemical and non-photochemical quenching of chlorophyll fluorescence by low concentrations of m-dinitrobenzene.

Chlorophyll fluorescence quenching induced by low concentrations of m-dinitrobenzene (DNB) is investigated. In intact spinach chloroplasts DNB causes photochemical and non-photochemical quenching. The...

Clinical Trials [115 Associated Clinical Trials listed on BioPortfolio]

Effect of Helicobacter Pylori on the Availability of Vitamin E and C

This study argues that H.pylori infection, by increasing the production of reactive oxygen species, increases the utilization of dietary antioxidants(Vit E and Vit C) that serve in quenchi...

Kinetics of D-Dimers After Abdominal Surgery

The purpose of this study is to investigate the natural kinetics of D-dimers that occur after abdominal surgery.

Measurement of Digital Colposcopy for Fluorescence Spectroscopy of Cervical Intraepithelial Neoplasia

The overall objective of this study is to identify potential improvements for a noninvasive method of diagnosing dysplasia and neoplasia in the cervix using digital colposcopy for colposco...

The Investigation of a Fluorescence/Elastic Scattering Spectroscopy (F-ESS) Device for Oral Tissue Characterization

The overall objective of this work is to identify changes in the optical properties of oral tissues to develop a non-invasive tool for the detection, diagnosis and screening of oral pathol...

A Feasibility Study to Assess Critical Aspects of Fluorescence Affinity Sensor (FAS) Performance and Safety Over Several Hours

The goal of this clinical research study is to learn about a new minimally invasive glucose monitoring device called Fluorescence Affinity Sensor (FAS). In this study, the FAS will be used...

Medical and Biotech [MESH] Definitions

Dimers found in DNA chains damaged by ULTRAVIOLET RAYS. They consist of two adjacent PYRIMIDINE NUCLEOTIDES, usually THYMINE nucleotides, in which the pyrimidine residues are covalently joined by a cyclobutane ring. These dimers block DNA REPLICATION.

Measurement of the intensity and quality of fluorescence.

An analytical method for detecting and measuring FLUORESCENCE in compounds or targets such as cells, proteins, or nucleotides, or targets previously labeled with FLUORESCENCE AGENTS.

A type of FLUORESCENCE SPECTROSCOPY using two FLUORESCENT DYES with overlapping emission and absorption spectra, which is used to indicate proximity of labeled molecules. This technique is useful for studying interactions of molecules and PROTEIN FOLDING.

The simultaneous identification of all chromosomes from a cell by fluorescence in situ hybridization (IN SITU HYBRIDIZATION, FLUORESCENCE) with chromosome-specific florescent probes that are discerned by their different emission spectra.

Search BioPortfolio: