Rapid Electrochemical Detection of Escherichia Coli Using a Rotating Disc Electrode

A novel electrochemical method was developed to detect the concentration of Escherichia coli (E.coli) in water. Chronoamperometry was used to record the electrochemical current response from different E.coli concentrations based on their interaction with a locally formed electrocatalyst, which occurs when a fixed potential is applied. A number of current responses that are specific to some known E.coli concentrations were recorded and used to develop a linear least squares regression model. The probe founded on this model had a detection limit of 105 CFU/ml and percent error consistently less than 15% on log scale with a detection time of 10 minutes. The major advantage of this sensor lies in its rapid detection and simplicity in detection mechanism, since the catalyst can be produced locally as and when required. Keywords: Electrochemical sensor; Escherichia coli detection; Rotating Disc electrode