An impedimetric glucose biosensor based overoxidezed polypyrrole thin film

Polypyrrole (pPy) thin films were synthesized electrochemically by a pulse method on platinum electrodes in Nbutyl- N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquid (PYR14TFSI). An important aspect of this procedure is the use of an ionic liquid, as synthetic medium. Further, it can be used for several procedures and it can then be renewed and recycled by a simple extraction just with warm water. It is therefore possible to remove it from all the residual oxidized pyrrolic compounds and purify the solvent in a very simplicistic way. After the synthesis pPy was overoxidized (opPy ) and the process was followed by EIS (Electrochemical Impedance Spectroscopy). opPy is attractive for the realization of sensors and biosensors because of its good selectivity towards hydrogen peroxide (H2O2) with respect to the most common interferents. In particular it can find an application in food process control. The EIS response to hydrogen peroxide and biological interferents indicated opPy as a highly sensitive electrochemical platform for impedimetric sensing. The glucose oxidase enzyme (GOD) was immobilized onto the polymer and the modified electrode was assembled and tested as an impedimetric biosensor. This technique seems very promising for application in food process control.