An assembled hematin is formed by depositing hematin on an electrically charged
substrate in one or more layers alternating with one or more layers of polyelectrolyte,
preferably a cationic polymer. In a method for polymerizing an aromatic monomer,
the assembled hematin is contacted with the monomer and a template, preferably
an anionic polymer. In a method for polymerizing aniline, the aniline, sulfonated
multi walled carbon nano tubes, PEG hematin and a reaction initiator are dispersed
in water.