title: Label-free photoelectrochemical detection of double-stranded HIV DNA by means of a metallointercalator-functionalized electrogenerated polymer.
abstract: The design of photoactive functionalized electrodes for the sensitive transduction of double-stranded DNA hybridization is reported. Multifunctional complex [Ru(bpy-pyrrole)2 (dppn)](2+) (bpy-pyrrole=4-methyl-4'-butylpyrrole-2,2'-bipyridine, dppn=benzo[i]dipyrido[3,2-a:2',3'-c]phenazine) exhibiting photosensitive, DNA-intercalating, and electropolymerizable properties was synthesized and characterized. The pyrrole groups undergo oxidative electropolymerization on planar electrodes forming a metallopolymer layer on the electrode. Thanks to the photoelectrochemical and intercalating properties of the immobilized Ru(II) complex, the binding of a double-stranded HIV DNA target was photoelectrochemically detected on planar electrodes. Photocurrent generation through visible irradiation was correlated to the interaction between double-stranded DNA and the metallointercalator polymer. These interactions were well fitted by using a Langmuir isotherm, which allowed a dissociation constant of 2×10(6)  L mol(-1) to be estimated. The low detection limit of 1 fmol L(-1) and sensitivity of 0.01 units per decade demonstrate excellent suitability of these modified electrodes for detection of duplex DNA.
authors.affiliation: Université Grenoble Alpes - CNRS, DCM UMR 5250, 38000 Grenoble (France).
authors.forename: Fatima
authors.initials: F
authors.lastname: Haddache
authors.forename: Alan
authors.initials: A
authors.lastname: Le Goff
authors.forename: Bertrand
authors.initials: B
authors.lastname: Reuillard
authors.forename: Karine
authors.initials: K
authors.lastname: Gorgy
authors.forename: Chantal
authors.initials: C
authors.lastname: Gondran
authors.forename: Nicolas
authors.initials: N
authors.lastname: Spinelli
authors.forename: Eric
authors.initials: E
authors.lastname: Defrancq
authors.forename: Serge
authors.initials: S
authors.lastname: Cosnier
mesh_terms: D015082:2,2'-Dipyridyl / Q000737:chemistry; D015374:Biosensing Techniques; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry; D004247:DNA / Q000032:analysis*; D055664:Electrochemical Techniques; D004566:Electrodes; D006678:HIV / Q000235:genetics*; D006801:Humans; D007364:Intercalating Agents / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D007364:Intercalating Agents; D011108:Polymers; D015082:2,2'-Dipyridyl; D012428:Ruthenium; D004247:DNA
keywords: DNA; biosensors; electropolymerization; intercalation; ruthenium