Biopolymers, Bio-related Polymer Materials

Metal nanoarchitecture fabrication using DNA as a biotemplate

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Among the many important biopolymers, DNA has been a key component in material sciences and nanotechnology. We have focused on the fabrication of metal nanoarchitectures using DNA as a template due to its intrinsic properties and advantages, such as a well-ordered structure, rich chemical functionality and programmable base-pairing interactions, as well as the availability of multiple enzymes for DNA manipulation. In this review, various methods for the fabrication of DNA-templated metal nanoarchitecture are introduced. The methods include DNA-mediated metal nanoparticle formation, DNA-templated conductive nanowire fabrication by metal depositions, sequence-selective metal deposition onto DNA for elaborate nanowire fabrication and DNA brushes as templates for use on solid substrates. DNA sequence-selective binding of metal ions and metal complexes and subsequent reduction to metals are fundamental issues for the fabrication of metal nanoarchitectures. The resultant metal nanoparticles and their assemblies can be used as functional nanomaterials in applications such as catalysts, conducting nanowires, optical nanomaterials and especially in metamaterials. This biopolymer-templating method can be applied not only to metal deposition but also to the assembly of functional molecules.

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This work was supported in part by the ‘Dynamic Alliance for Open Innovation Bridging Human, Environment and Materials’ from the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT). This work was performed under the Cooperative Research Program of the ‘Network Joint Research Center for Materials and Devices’. A part of this work was conducted at Hokkaido University, supported by the ‘Nanotechnology Platform’ Program of the MEXT, Japan. Support from the Noguchi Institute (HM) is also acknowledged.

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Correspondence to Kuniharu Ijiro.

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