title: A gold nanoparticle based approach for screening triplex DNA binders.
abstract: Nanoparticle assemblies interconnected with DNA triple helixes can be used to colorimetrically screen for triplex DNA binding molecules and simultaneously determine their relative binding affinities based on melting temperatures. Nanoparticles assemble only when DNA triple helixes form between DNA from two different particles and a third strand of free DNA. In addition, the triple helix structure is unstable at room temperature and only forms in the presence of triplex DNA binding molecules which stabilize the triple helix. The resulting melting transition of the nanoparticle assembly is much sharper and at a significantly higher Tm than the analogous triplex structure without nanoparticles. Upon nanoparticle assembly, a concomitant red-to-blue color change occurs. The assembly process and color change do not occur in the presence of duplex DNA binders and therefore provide a significantly better screening process for triplex DNA binding molecules compared to standard methods.
authors.affiliation: Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA.
authors.forename: Min Su
authors.initials: MS
authors.lastname: Han
authors.forename: Abigail K R
authors.initials: AK
authors.lastname: Lytton-Jean
authors.forename: Chad A
authors.initials: CA
authors.lastname: Mirkin
mesh_terms: D001483:Base Sequence; D001600:Berberine Alkaloids / Q000032:analysis* / Q000737:chemistry; D003124:Colorimetry / Q000379:methods; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D007211:Indoles / Q000032:analysis* / Q000737:chemistry; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry*; D009693:Nucleic Acid Hybridization; D009841:Oligonucleotides / Q000737:chemistry / Q000378:metabolism; D011725:Pyridines / Q000032:analysis* / Q000737:chemistry
chemical_list: D001600:Berberine Alkaloids; D007211:Indoles; D009841:Oligonucleotides; D011725:Pyridines; C051802:triplex DNA; C082732:3-methoxy-7H-8-methyl-11-((3'-amino)propylamino)benzo(e)pyrido(4,3-b)indole; C000666:coralyne; D006046:Gold; D004247:DNA