Gated amperometry methods

摘要

A sensor system, device, and methods for determining the concentration of an analyte in a sample is described. Gated amperometric pulse sequences including multiple duty cycles of sequential excitations and relaxations may provide a shorter analysis time and/or improve the accuracy and/or precision of the analysis. The disclosed gated amperometric pulse sequences may reduce analysis errors arising from the hematocrit effect, variance in cap-gap volumes, non-steady-state conditions, mediator background, under-fill, temperature changes in the sample, and a single set of calibration constants.

主权项

1. A method of reducing bias attributable to mediator background in a determined concentration of an analyte in a sample comprising:
generating a measurable species from a mediator, the concentration of the measurable species responsive to a concentration of an analyte in a sample; applying an input signal to the sample, the input signal comprising at least 3 duty cycles within 180 seconds and each duty cycle comprising an excitation and a relaxation,
where the input signal has a redox intensity of at least 0.01 if continued for a 10 second duration,where the relaxations of the at least 3 duty cycles each provide an independent diffusion and analyte reaction time during which the analyte generates the measurable species; measuring an output signal from at least one amperometric excitation of the at least 3 duty cycles,
the output signal responsive to the concentration of the measurable species in the sample, andthe at least one amperometric excitation having a duration from 0.01 second to 1.5 seconds; and determining the concentration of the analyte in the sample having reduced bias attributable to mediator background in response to the measured output signal, where the determined concentration is responsive to a rate at which the measurable species is oxidized or reduced by the input signal.