Abstract: Methods and devices for performing in situ hematocrit adjustments during glucose testing using glucose-monitoring products and using those adjusted values to estimate the hematocrit value of blood samples to reduce or eliminate the assay bias caused by the different hematocrit levels of blood samples. One method involves measuring the glucose value, Glum, of the blood sample; measuring the resistance of the blood sample (Rcell) using a biosensor reagent; measuring the resistance of plasma (Rplasma) using the biosensor reagent; determining the calculated resistance of red blood cells, RRBC, of the blood sample according to the relationship RRBC=Rcell?Rplasma; calculating the percent hematocrit, % Hctc, of the blood sample; determining whether to adjust the glucose value, Glum, to an adjusted glucose value, Gluadj; and using the percent hematocrit, % Hctc, and either the glucose value, Glum, or the adjusted glucose value, Gluadj, to adjust for any bias of the biosensor reagent.

Abstract: Methods and devices for performing in situ hematocrit adjustments during glucose testing using glucose-monitoring products and using those adjusted values to estimate the hematocrit value of blood samples to reduce or eliminate the assay bias caused by the different hematocrit levels of blood samples. One method involves measuring the glucose value, Glum, of the blood sample; measuring the resistance of the blood sample (Rcell) using a biosensor reagent; measuring the resistance of plasma (Rplasma) using the biosensor reagent; determining the calculated resistance of red blood cells, RRBC, of the blood sample according to the relationship RRBC=Rcell?Rplasma; calculating the percent hematocrit, % Hctc, of the blood sample; determining whether to adjust the glucose value, Glum, to an adjusted glucose value, Gluadj; and using the percent hematocrit, % Hctc, and either the glucose value, Glum, or the adjusted glucose value, Gluadj, to adjust for any bias of the biosensor reagent.

Abstract: A method of determining the concentration of an analyte in a fluid test sample that includes providing an electrochemical sensor adapted to measure the analyte in the test sample. The test sample sufficiently covers a counter and working electrode of the electrochemical sensor. A first potential is applied between the counter and working electrodes for a first predetermined time period and the current is measured and the time is recorded. After the first potential is removed or substantially reduced, a second potential is applied between the counter and working electrodes and the current is measured. The concentration of the analyte is determined in the test sample as a function of the current measured. An index is calculated and compared to at least one predetermined parameter to identify when a bias, if any, exceeds a threshold. An error signal or analyte concentration is displayed depending on the comparison.

Abstract: Disclosed is an improved electrochemical sensor for the detection of an analyte in a fluid test sample. The electrochemical sensor is of the type in which the fluid test sample is drawn into a capillary space and the improvement to the sensor involves an arrangement where a portion of the sensor's counter electrode is placed on the edge of the capillary space in a relationship to the sensor's working electrode such that if the capillary space is not completely filled there will be generated only a very weak current. When the sensor is connected to a properly programmed current detector, the weak current caused by the underfilling of the capillary space will be detected as an error and will notify the user of the sensor that the test should not be continued.

Abstract: Disclosed is an improved electrochemical sensor for the detection of an analyte in a fluid test sample. The electrochemical sensor is of the type in which the fluid test sample is drawn into a capillary space and the improvement to the sensor involves an arrangement where a portion of the sensor's counter electrode is placed on the edge of the capillary space in a relationship to the sensor's working electrode such that if the capillary space is not completely filled there will be generated only a very weak current. When the sensor is connected to a properly programmed current detector, the weak current caused by the underfilling of the capillary space will be detected as an error and will notify the user of the sensor that the test should not be continued.

Abstract: A method of determining the concentration of an analyte in a fluid test sample that includes providing an electrochemical sensor adapted to measure the analyte in the test sample. The test sample sufficiently covers a counter and working electrode of the electrochemical sensor. A first potential is applied between the counter and working electrodes for a first predetermined time period and the current is measured and the time is recorded. After the first potential is removed or substantially reduced, a second potential is applied between the counter and working electrodes and the current is measured. The concentration of the analyte is determined in the test sample as a function of the current measured. An index is calculated and compared to at least one predetermined parameter to identify when a bias, if any, exceeds a threshold. An error signal or analyte concentration is displayed depending on the comparison.

Abstract: Disclosed is an improved electrochemical sensor for the detection of an analyte in a fluid test sample. The electrochemical sensor is of the type in which the fluid test sample is drawn into a capillary space and the improvement to the sensor involves an arrangement where a portion of the sensor's counter electrode is placed on the edge of the capillary space in a relationship to the sensor's working electrode such that if the capillary space is not completely filled there will be generated only a very weak current. When the sensor is connected to a properly programmed current detector, the weak current caused by the underfilling of the capillary space will be detected as an error and will notify the user of the sensor that the test should not be continued.

Abstract: Disclosed is an electrochemical sensor which is made up of an insulating base plate bearing an electrode on its surface which reacts with an analyte to produce mobile electrons. The base plate is mated with a lid of a deformable material which has a concave area surrounded by a flat surface so that when mated to the base plate there is formed a capillary space into which a fluid test sample can be drawn. The side of the lid facing the base is coated with a polymeric material which serves to bond the lid to the base plate and to increase the hydrophilic nature of the capillary space.

Abstract: Disclosed is an improved electrode suitable for the electrochemical regeneration of the co-enzymes NADH and NADPH. The electrode has imparted on its surface a mediator function which is a 3-phenylimino-3H-phenothiazine or a 3-phenylimino-3H-phenoxazine. Also disclosed is a method of improving the performance of a biochemical fuel cell which operates with a dehydrogenase as a catalyst and a co-enzyme as the energy-transferring redox couple which involves using the improved electrode in the fuel cell.