Desired immobilization of biomolecules on PAni substrates is
achieved through molecular entrapment, protein A adsorption,
electrostatic binding by oxidation and covalent bonding to the
copolymerized PAni [10–15]. Enzymes have also been grafted onto
the PAni surface with the help of cross-linkers [16–19]. At times, for
immobilizing the biomolecules, PAni is first grafted with suitable
functional groups, e.g.–COOH using acrylic acid [20,21]. One of our
recent works demonstrated the immobilization of protein
molecules on PAni through avidin-biotin interaction [22]