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Reversible structural switching of a DNA-DDAB film.

ABSTRACT: We describe the novel structure and behavior of a DNA-DDAB complex film cast from an organic solvent and exhibiting a structural switching transition as it is dried or wetted with water. The film was easily prepared by formation of a complex between the negatively charged phosphate groups of DNA and the positively charged headgroup of the surfactant DDAB. This complex was then purified, dried, dissolved in 2-propanol, and cast onto a glass slide to form a self-standing film by means of slow evaporation. While the structure of the dried film was found to be composed of single-stranded DNA and a monolayer of DDAB, upon hydration of the film, the structure switched to double-stranded DNA complexed to a bilayer of DDAB. We expect this phenomenon to serve as a useful model for the design of new responsive materials and programmable self-assembly.

SUBMITTER: Neumann T

PROVIDER: S-EPMC2664520 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Reversible structural switching of a DNA-DDAB film.

Neumann Thorsten T Gajria Surekha S Tirrell Matthew M Jaeger Luc L

Journal of the American Chemical Society 20090301 10

We describe the novel structure and behavior of a DNA-DDAB complex film cast from an organic solvent and exhibiting a structural switching transition as it is dried or wetted with water. The film was easily prepared by formation of a complex between the negatively charged phosphate groups of DNA and the positively charged headgroup of the surfactant DDAB. This complex was then purified, dried, dissolved in 2-propanol, and cast onto a glass slide to form a self-standing film by means of slow evap ...[more]

PMID: 19275252

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