title: Oxidative cleavage of DNA by pentamethine carbocyanine dyes irradiated with long-wavelength visible light.
abstract: Here we report the synthesis of seven symmetrical carbocyanine dyes in which two nitrogen-substituted benz[e]indolium rings are joined by a pentamethine bridge that is meso-substituted with chlorine or bromine versus hydrogen. The heteroatom of benz[e]indolium is modified with a phenylpropyl, methyl, or cationic quaternary ammonium group. In reactions containing micro molar concentrations of halogenated dye, irradiation at 575, 588, 623, or 700nm produces good photocleavage of plasmid DNA. UV-visible spectra show that the carbocyanines are in their H-aggregated and monomeric forms. Scavenger experiments point to the involvement of singlet oxygen and hydroxyl radicals in DNA photocleavage.
authors: Department of Chemistry, The Center for Diagnostics and Therapeutics, The Center for Biotechnology and Drug Design, Georgia State University, Atlanta, GA 30302-3965, USA. Electronic address: cterry2@student.gsu.edu.
authors: Carla T
authors: CT
authors: Mapp
authors: Department of Chemistry, The Center for Diagnostics and Therapeutics, The Center for Biotechnology and Drug Design, Georgia State University, Atlanta, GA 30302-3965, USA. Electronic address: eowens9@student.gsu.edu.
authors: Eric A
authors: EA
authors: Owens
authors: Department of Chemistry, The Center for Diagnostics and Therapeutics, The Center for Biotechnology and Drug Design, Georgia State University, Atlanta, GA 30302-3965, USA. Electronic address: mhenary1@gsu.edu.
authors: Maged
authors: M
authors: Henary
authors: Department of Chemistry, The Center for Diagnostics and Therapeutics, The Center for Biotechnology and Drug Design, Georgia State University, Atlanta, GA 30302-3965, USA. Electronic address: kbgrant@gsu.edu.
authors: Kathryn B
authors: KB
authors: Grant
mesh_terms: D002232:Carbocyanines / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D053837:DNA Cleavage; D015394:Molecular Structure; D010084:Oxidation-Reduction; D013056:Spectrophotometry, Ultraviolet; D014466:Ultraviolet Rays
chemical_list: D002232:Carbocyanines; D004396:Coloring Agents; D004247:DNA
keywords: ()OH; (1)O(2); (3)O(2); (3-bromopropyl)trimethylammonium bromide; Benz[e]indolium; CT; Carbocyanine; DNA base pairs; LED; PDT; Photocleavage; Photodynamic therapy; ROS; Red light; TMAB; TO; Tri-cationic; YO; bp; calf thymus; ground state triplet molecular oxygen; hydroxyl radical; light emitting diode; oxazole yellow; photodynamic therapy; reactive oxygen species; singlet oxygen; thiazole orange