Biosensor designs are emerging at a significant rate and play an increasingly important role in foodborne pathogen
detection. Conducting polymers are excellent tools for the fabrication of biosensors and polypyrrole has been used in the
detection of biomolecules due to its unique properties. The prime intention of this paper was to pioneer the design and
fabrication of a single-strand (ss) DNA biosensor for the detection of the <i>Bacillus cereus</i> (<i>B.cereus</i>) group species.
Growth of <i>B. cereus</i>, results in production of several highly active toxins. Therefore, consumption of food containing
>10<sup>6</sup> bacteria/gm may results in emetic and diarrhoeal syndromes. The most common source of this bacterium is found
in liquid food products, milk powder, mixed food products and is of particular concern in the baby formula industry.
The electrochemical deposition technique, such as cyclic voltammetry, was used to develop and test a model DNA-based
biosensor on a gold electrode electropolymerized with polypyrrole. The electrically conducting polymer, polypyrrole is
used as a platform for immobilizing DNA (1μg) on the gold electrode surface, since it can be more easily deposited from
neutral pH aqueous solutions of pyrrolemonomers. The average current peak during the electrodeposition event is
288μA. There is a clear change in the current after hybridization of the complementary oligonucleotide (6.35μA) and for
the noncomplementary oligonucleotide (5.77μA). The drop in current after each event was clearly noticeable and it
proved to be effective.