Conducting polymer-coated Physarum polycephalum towards the synthesis of bio-hybrid electronic devices

Abstract

This paper presents a generic method for the production of functionalized coatings on biological substrates. The specific method described involves the functionalization of the living plasmodial stage of Physarum polycephalum with the conducting organic polymer polypyrrole. The simple method involves localized treatment of tube sections with a solution of ferric chloride, followed by exposure to the vapour or a liquid solution of the pyrrole monomer. This technique enables the production of surface-coated conducting plasmodial tubes of certain lengths to be formed at specific points. Measurement of the electrical resistance of a 1 cm functionalized tube gave a value of 100 k$\mathrm{\Omega }$. The use of this selective functionalization technique means that the majority of the growing plasmodium remains unfunctionalized and living; thus, a true hybrid device is formed. It can be seen how a range of functionalized polymers and materials whereby a chemical activator, for the formation of the product (or the pre-cursor) can be added to P. polycephalum (or other organisms) followed by reaction to form a hybrid material.

Keywords:

• polypyrrole
• plasmodium
• chemical polymerization
• conducting wire

Additional information

Funding

The authors BC and AA were supported by the EU research project Physarum Chip: Growing Computers from Slime Mould (FP7 ICT Ref 316366).