Enzymatic Synthesis of Conductive Polymers

Enzymatic synthesis of conductive polymers harnesses the catalytic power of oxidoreductase enzymes—principally laccases and peroxidases—to polymerise aromatic monomers under mild, aqueous conditions. By using molecular oxygen or in situ-generated hydrogen peroxide as oxidants, these biocatalytic routes avoid harsh acids and heavy-metal catalysts typical of chemical or electrochemical polymerisation. Templates such as vesicles, micelles or polyelectrolytes guide chain growth and favour the formation of the emeraldine salt form of polyaniline, conferring high electrical conductivity, redox activity and processable nanostructures. Cascade reactions combining oxidases and peroxidases further enhance efficiency by generating oxidant in situ. The resulting polymers and composites find application in energy storage, flexible electronics, sensors and conductive textiles, while aligning with circular and green-chemistry principles through low waste, ambient conditions and renewable biocatalysts.

Research from Nature Portfolio

Recent studies have used vesicle-assisted laccase catalysis to oxidatively oligomerise aniline dimers in aqueous media. Small anionic vesicles of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) serve as soft templates, controlling radical coupling and suppressing precipitation. In situ Raman spectroscopy, alongside UV/vis/NIR and EPR analyses, has confirmed the formation of polymeric products resembling the conductive emeraldine salt of polyaniline. Moreover, direct coating of as-prepared vesicle suspensions onto electrodes demonstrated stable redox activity not only under strongly acidic conditions but also at neutral pH, expanding the operational window for bio-fabricated conductive films.

Enzymatic Synthesis of Conductive Polymers publication trend

The graph below shows the total number of articles in enzymatic synthesis of conductive polymers across all publications each year (not limited to Nature Index journals).

Technical terms

Laccase: A multicopper oxidase that catalyses one-electron oxidations of phenolic and aniline substrates using O₂ as electron acceptor.

Peroxidase: An enzyme that drives oxidation of organic monomers by reducing hydrogen peroxide to water.

Emeraldine salt: The half-oxidised, protonated form of polyaniline exhibiting high electrical conductivity and characteristic green colour.

Template-assisted synthesis: Use of vesicles, micelles or polymers to spatially organise radical intermediates and guide polymer chain assembly.

Enzymatic cascade: Sequential enzyme reactions in a single mixture where one enzyme’s product serves as the substrate or co-reactant for the next, enhancing overall efficiency.

References

1. Enzymatic oligomerization and polymerization of arylamines: state of the art and perspectives. Chemical Papers (2016).
2. Synthesizing Polyaniline With Laccase/O2 as Catalyst. Frontiers in Bioengineering and Biotechnology (2019).
3. Insight into the template effect of vesicles on the laccase-catalyzed oligomerization of N-phenyl-1,4-phenylenediamine from Raman spectroscopy and cyclic voltammetry measurements. Scientific Reports (2016).
4. Application of an enzymatic cascade reaction for the synthesis of the emeraldine salt form of polyaniline. Chemical Papers (2021).
5. Hemin-catalyzed oxidative oligomerization of p -aminodiphenylamine (PADPA) in the presence of aqueous sodium dodecylbenzenesulfonate (SDBS) micelles. RSC Advances (2022).