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Abstract: Double-stranded DNA is one of functional polymers, but the large amounts of DNA sources, such as salmon milt and shellfish gonads, have been discarded as industrial wastes. Therefore, conversion of this discarded DNA to be a useful material would be beneficial to utilize the unique property of DNA. These materials including DNA have been prepared by mixing with the organic polymers, such as alginic acid, collagen, and chitosan. However, since these materials have consisted from entirely organic components, these do not have the mechanical strength for a material. So, we prepared the organic–inorganic hybrid materials by mixing DNA with silane coupling reagents bis(trimethoxysilylpropyl)amine or bis[(3-trimethoxysilyl)propyl]ethylenediamine. These hybrid materials with the flexibility were water-insoluble and resistant to hydrolysis by nuclease. In addition, the mechanical strength of this hybrid material was approximately twice as high as that of DNA without mixing with silane coupling reagents. Furthermore, the double-stranded DNA in the hybrid materials has been maintained in a B-form structure in aqueous solution. Thus, we demonstrated the utilization of DNA as a functional material. As a result, this material could selectively accumulate harmful DNA-intercalating compounds with the planar structure, such as dibenzo-p-dioxin, dibenzofuran, and ethidium bromide. Organic–inorganic hybrid material including double-stranded DNA has potential to serve as a useful biomaterial for medical, engineering, and environmental applications. [Copyright &y& Elsevier]

Abstract: Large amounts of DNA-enriched biomaterials, such as salmon milts and shellfish gonads, are discarded as industrial waste around the world. We could convert the discarded DNA into a novel bio-matrix by the hybridization of DNA and metal ions, such as Al3+, Cr3+, Fe2+, Fe3+, Cu+, Cu2+, Zn2+, and Cd2+. These water-insoluble DNA-metal ion matrices could be created in various desirable forms, such as a gel, capsule, film, or fiber. DNA-Al3+ matrices were found to maintain a B-form DNA structure, which was the native double-stranded DNA structure in water. The DNA-Al3+ fiber showed flexibility with the molecular orientation in the direction of drawing. When a DNA-Cu2+ matrix was incubated in an aqueous hydroquinone or ascorbic acid solution, benzoquinone or dehydroascorbic acid was produced, respectively, by the oxidative effect of Cu2+ in the DNA-metal ion matrix. These results suggest that metal ions in the DNA-metal matrix maintained the oxidative function. The water-insoluble DNA-metal ion matrices may have a potential utility as a functional bio-material, such as an antibacterial, oxidative, bio-sensor, and ion conductive materials. [Copyright &y& Elsevier]