title: Preparation and characterization of DNA films induced by UV irradiation.
abstract: Large amounts of DNA-enriched materials, such as salmon milts and shellfish gonads, are discarded as industrial waste. We have been able to convert the discarded DNA to a useful material by preparing novel DNA films by UV irradiation. When DNA films were irradiated with UV light, the molecular weight of DNA was greatly increased. The reaction was inhibited by addition of the radical scavenger galvinoxyl suggesting that the DNA polymerization with UV irradiation proceeded by a radical reaction. Although this UV-irradiated DNA film was water-insoluble and resistant to hydrolysis by nuclease, the structure of the DNA film in water was similar to non-irradiated DNA and maintained B-form structure. In addition, the UV-irradiated DNA film could effectively accumulate and condense harmful DNA-intercalating compounds, such as ethidium bromide and acridine orange, from diluted aqueous solutions. The binding constant and exclusion number of ethidium bromide for UV-irradiated DNA were determined to be 6.8 +/- 0.3 x 10(4) M(-1) and 1.6 +/- 0.2, respectively; these values are consisted with reported results for non-irradiated DNA. The UV-irradiated DNA films have potential uses as a biomaterial filter for the removal of harmful DNA intercalating compounds.
authors.affiliation: Laboratory of Bio-Material, Chemistry Division of Bioscience, Graduate School of Environmental Earth Science, Hokkaido University, Kita-10, Nishi-5, Kita-ku, Sapporo 060-0810, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Yamada
authors.forename: Kozue
authors.initials: K
authors.lastname: Kato
authors.forename: Motoyoshi
authors.initials: M
authors.lastname: Nomizu
authors.forename: Nobuo
authors.initials: N
authors.lastname: Sakairi
authors.forename: Kousaku
authors.initials: K
authors.lastname: Ohkawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Norio
authors.initials: N
authors.lastname: Nishi
mesh_terms: D000165:Acridine Orange / Q000737:chemistry; D000818:Animals; D003247:Conservation of Natural Resources; D004247:DNA / Q000737:chemistry* / Q000528:radiation effects; D004996:Ethidium / Q000737:chemistry; D007220:Industrial Waste / Q000517:prevention & control*; D007364:Intercalating Agents; D009690:Nucleic Acid Conformation / Q000528:radiation effects; D012995:Solubility; D014466:Ultraviolet Rays
chemical_list: D007220:Industrial Waste; D007364:Intercalating Agents; D004247:DNA; D004996:Ethidium; D000165:Acridine Orange