One step biosynthesis of chiral, conducting and water soluble polyaniline in AOT micellar solution

Horseradish peroxidase (HRP)/H2O2-triggered polymerization of aniline in sodium bis-(2-ethylhexyl)sulfosuccinate (AOT) micellar solution is first presented. Results show that the critical micelle concentration of AOT in the polymerization system is very low and AOT has small effect on the activity of HRP, so it matches with HRP well for the end. As a template, the AOT micellar solution is essential for the formation of conducting polyaniline. In the present system, AOT also acts as a dopant and a dispersant, leading to the formation of conducting and water soluble polyaniline. Optimization of the pH and the H2O2 concentration results in more conducting polyaniline. During investigation, it was found that HRP itself can induce the formation of chiral polyaniline without any other chiral inducer. In short, with the aid of AOT, one-step biosynthesis of chiral, conducting and water soluble polyaniline using HRP as both catalyst and chiral inducer is realized. Compared with other aniline polymerization systems reported elsewhere, the present system shows many advantages. It needs less templates and no foreign chiral inducer while the synthesized polyaniline has good dispersibility and high electrical conductivity.