Biochemical synthesis and unusual conformational switching of a molecular complex of polyaniline and DNA

摘要

Polyaniline (Pani) is one of the most interesting conducting polymers because of its promising electrical properties and unique redox tunability. Recently a new template assisted, enzymatic synthetic approach has been developed which yields a water-soluble and conducting complex of polyaniline and the template used. The mild reaction conditions in this approach allow for the utilization of delicate biological systems as template materials, such as DNA. Here we report the extension of this enzymatic approach to the synthesis of Pani on a DNA matrix. DNA serves as a suitable template for complexation and formation of conducting polyaniline. The redox behavior of Pani induces reversible conformational change in the secondary structure of DNA. Circular dichroism results suggest that the secondary structure of the DNA may be reversibly switched through manipulation of the redox state of the polyaniline.