Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2008-2-20
pubmed:abstractText
Photoelectrochemical sensors were developed for the rapid detection of oxidative DNA damage induced by Fe2+ and H2O2 generated in situ by the enzyme glucose oxidase. The sensor is a multilayer film prepared on a tin oxide nanoparticle electrode by layer-by-layer self-assembly and is composed of separate layers of a photoelectrochemical indicator, DNA, and glucose oxidase. The enzyme catalyzes the formation of H2O2 in the presence of glucose, which then reacts with Fe2+ and generates hydroxyl radicals by the Fenton reaction. The radicals attack DNA in the sensor film, mimicking metal toxicity pathways in vivo. The DNA damage is detected by monitoring the change of photocurrent of the indicator. In one sensor configuration, a DNA intercalator, Ru(bpy)2(dppz)2+ (bpy = 2,2'-bipyridine, dppz = dipyrido[3,2-a:2',3'-c]phenazine), was employed as the photoelectrochemical indicator. The damaged DNA on the sensor bound less Ru(bpy)2(dppz)2+ than the intact DNA, resulting in a drop in photocurrent. In another configuration, ruthenium tris(bipyridine) was used as the indicator and was immobilized on the electrode underneath the DNA layer. After oxidative damage, the DNA bases became more accessible to photoelectrochemical oxidation than the intact DNA, producing a rise in photocurrent. Both sensors displayed substantial photocurrent change after incubation in Fe2+/glucose in a time-dependent manner. And the detection limit of the first sensor was less than 50 microM. The results were verified independently by fluorescence and gel electrophoresis experiments. When fully integrated with cell-mimicking components, the photoelectrochemical DNA sensor has the potential to become a rapid, high-throughput, and inexpensive screening tool for chemical genotoxicity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0013-936X
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
635-9
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Photoelectrochemical sensor for the rapid detection of in situ DNA damage induced by enzyme-catalyzed fenton reaction.
pubmed:affiliation
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't