摘要 |
An amperometric glucose biosensor having high sensitivity and accuracy over a wide range of glucose concentrations and a method for the rapid detection of glucose in urine are provided. The biosensor strip comprises an electrically conductive carbon layer, having a first redox mediator, a reagent strip containing an enzyme system for the oxidation of glucose and a second redox mediator, and a silver/silver chloride reference electrode. In a preferred form of the sensor that has high sensitivity, a sensing electrode and a reference electrode are arranged so that the electrically conductive layers of the electrodes are face-to-face and sandwich the reagent strip between them. Screening for glucose is achieved by contacting the sensor with a drop of the patient's urine and comparing the current read-out with a standard calibration curve or by automatically converting the current flow generated by the test sample to units of glucose concentration. The sensor can measure urine glucose concentrations below 3 mg/dl. Measurement of urine glucose concentration with the sensor provides a non-invasive probe of a patient's blood glucose level since a linear relationship exists between blood glucose concentration and urine glucose concentration, approximately in the range between 0 to 400 mg/dl.
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