title: The effect of ethidium bromide on the liquid crystalline phases of aqueous DNA.
abstract: The influence of the intercalation of ethidium bromide (EB) on the characteristics of the DNA cholesteric and hexagonal mesophases is studied by optical microscopy, circular dichroism, and X-ray diffraction. The distance between DNA rods in the hexagonal phase is not modified by the presence of EB whereas the pitch of the cholesteric mesophase is considerably shortened by the dye. This seems to be related to the stereochemical effect of the intercalation rather than to the presence of a random distribution of the positive charge of the dye.
authors.affiliation: Dipartimento di Chimica Organica A. Mangini, Università di Bologna, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Gottarelli
authors.forename: G P
authors.initials: GP
authors.lastname: Spada
authors.forename: P
authors.initials: P
authors.lastname: Mariani
authors.forename: M
authors.initials: M
authors.lastname: Miranda de Morais
mesh_terms: D002942:Circular Dichroism; D003460:Crystallization; D004247:DNA / Q000737:chemistry*; D004996:Ethidium / Q000494:pharmacology*; D014961:X-Ray Diffraction
chemical_list: D004247:DNA; D004996:Ethidium