A system for calibrating an analyzer includes a test strip body. The system further includes a plurality of leads on the test strip body. The system further includes a circuit on the test strip body. The circuit includes a first resistor interconnected with at least a first portion of the plurality of leads and a second resistor interconnected with at least a second portion of the plurality of leads. When the test strip body is inserted into an analyzer, the circuit is configured to provide a signal simulating an electrochemical test strip.

Test sensors, methods, and systems are described that include a first electrode pair having either two active electrodes or an inactive working electrode paired with an active counter electrode. These active electrodes are different than having an electron transfer mediator on an inactive electrode because in addition to the structural differences between an electrode directly in contact with the conductors of the test sensor verses a reagent coating, there are chemical and functional differences. The active electrodes are formed from an electrode core material including an element that loses or acquires electrons during the analysis and directly participates in the electrochemical reaction of the sample. As the active electrodes are insoluble in the sample during the analysis, an electrochemically stable potential is provided by the active electrodes that can reliably operate at higher operating potentials than conventional electron transfer mediator reagents coated on an inactive electrode.

A cycle of positive and negative voltage pulses applied to an electrode sensor removes passivation of an electrode surface. The conditioned sensors have improved sensitivity to concentrations for analytes of interest. The electrode surfaces can also be passivated on purpose to reduce sensitivity. The voltages applied are varied according to the solution present.

Methods and devices for determining device usability, e.g., for point of care assay devices. In one embodiment, the invention is to a method of determining device usability in a sensing device, including the steps of: providing a device comprising a first electrical pad; a second electrical pad; and a first polymer layer contacting at least a portion of the first and the second electrical pads and a second polymer layer contacting the first polymer layer and not the first and second electrical pads; applying a potential across the first and the second electrical pads; measuring an electrical property associated with the first and the second polymer layers; and determining whether the measured electrical property associated with the first and the second polymer layers has exceeded a threshold level associated with the device usability.

Continuous glucose monitoring (CGM) may include applying a periodic excitation signal via an electrode of a CGM sensor to human interstitial fluid to drive an oxidation/reduction reaction, and measuring the current through the electrode. In some embodiments, the measured current is sampled and digitized, and various harmonics of the excitation signal's fundamental frequency are extracted. A set of relationships of at least two harmonics each is generated from the spectral amplitudes of a set of pairs, triplets, etc., of the harmonics, and the set of relationships is mapped to a glucose concentration such as based on the contents of a harmonic relationship database having a pre-existing set of harmonic relationships and glucose concentrations to which those sets of harmonic relationships correspond, for example. Numerous other embodiments are provided.

An electrochemical test strip, measurement system and method for determining sample content in the reactive region of the electrochemical test strip are presented. The electrochemical test strip comprises an insulator substrate which includes an electrode system disposed thereon. The electrode system includes at least one pair of electrodes. A lower plate which includes a reactive region and a sampling cell is disposed on the insulator substrate. An upper plate is disposed on the lower plate, wherein the at least one pair of electrodes is designed as an electrical loop adjacent to the sampling port.

Methods for calculating an analyte concentration of a sample are provided. In one exemplary embodiment the method includes steps that are directed toward accounting for inaccuracies that occur as a result of temperature variations in a sample, a meter, or the surrounding environment. In another exemplary embodiment the method includes steps that are directed toward determining whether an adequate sample is provided in a meter because insufficient samples can result in inaccuracies. The methods that are provided can be incorporated into a variety of mechanisms, but they are primarily directed toward glucose meters for blood samples and toward meters for controls solutions.

Test strip and method of operating thereof are provided. The test strip, from the top down, comprises a cover, an insulating layer, an electrode set, and a substrate. More particularly, the electrode set at least comprises a first electrode, a second electrode, and a third electrode. The insulating layer comprises a track, and the cover comprises an inlet, an indication line, and at least one vent. With the third electrode and the indication line in accordance with the present invention, a user may confirm the operation status of the test strip and the loading status of biological samples with ease to improve the accuracy of testing.

Test sensors, methods, and systems are described that include a first electrode pair having either two active electrodes or an inactive working electrode paired with an active counter electrode. These active electrodes are different than having an electron transfer mediator on an inactive electrode because in addition to the structural differences between an electrode directly in contact with the conductors of the test sensor verses a reagent coating, there are chemical and functional differences. The active electrodes are formed from an electrode core material including an element that loses or acquires electrons during the analysis and directly participates in the electrochemical reaction of the sample. As the active electrodes are insoluble in the sample during the analysis, an electrochemically stable potential is provided by the active electrodes that can reliably operate at higher operating potentials than conventional electron transfer mediator reagents coated on an inactive electrode.

A biosensor system determines analyte concentration from an output signal generated from a light-identifiable species or a redox reaction of the analyte. The biosensor system compensates at least 50% of the total error in the output signal with a primary function and may compensate a portion of the residual error with at least one residual function. A segmented signal processing (SSP) function may serve as the primary function, first residual function, or second residual function. Preferably, when the SSP function serves as the first residual function, the SSP function compensates at least 50% of the residual error remaining after primary compensation. Preferably, when the SSP function serves as the second residual function, the SSP function compensates at least 50% of the residual error remaining after primary and first residual compensation. The error compensation provided by the primary, first residual, and second residual functions may be adjusted with function weighing coefficients.