Patent ID: 7731835

Claim:
A method for monitoring analyte concentration in a biological fluid by use of a sensor, the method comprising the steps of: providing a sensor comprising a volume of a hydrophilic medium for retaining an amount of analyte proportionate to the concentration of analyte in a biological fluid in contact with the sensor, an enclosure for said analyte retention volume, an electrode in contact with the hydrophilic medium, a redox enzyme in contact with the medium, and a covalently bound electron transfer mediator that shifts between oxidized and reduced states for facilitating transfer of electrons between the enzyme and the electrode, the enzyme substantially not capable of transferring electrons to or from components of the biological fluid other than said analyte, contacting the biological fluid with the sensor and at initially predetermined intervals intermittently applying a potential to the electrode sufficient to oxidize the electron mediator and sensing current through said electrode during the application of the mediator oxidizing potential, maintaining the applied mediator oxidizing potential at least for a period of time sufficient to determine the rate of change of current with time through the electrode, correlating the current flow resulting from the applied mediator oxidizing potential with the current flow for known concentrations of said analyte in the retention medium, and between the intermittent applications of the mediator oxidizing potential, removing the applied mediator oxidizing potential from the electrode to stop oxidation of the mediator.