Glucose Biosensor Hematocrit Compensation via Segmented Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrochemical glucose test strips are affected by hematocrit variations in blood samples, leading to inaccurate glucose readings due to interference from red blood cells, which current strategies struggle to fully correct.
Innovation Solution
The use of a system with multiple electrodes and a microcontroller that applies specific electrical signals to measure both glucose concentration and hematocrit levels, allowing for accurate analyte determination by compensating for hematocrit effects through phase-shift-based measurements and calibration equations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional electrochemical test strips are used without hematocrit correction, then the device complexity is low, but measurement precision deteriorates due to hematocrit variations
Solution Approach 1:
The test strip is divided into functionally independent zones: a first test zone with glucose oxidase for glucose measurement, and a second test zone with hemoglobin-binding compounds for hematocrit measurement. This segmentation allows simultaneous measurement of both parameters without interference, resolving the contradiction between measurement precision and device complexity by integrating multiple functions into a single strip structure.
Solution Approach 2:
The test strip is designed to perform multiple functions: glucose concentration measurement in the first test zone and hematocrit level determination in the second test zone. This multi-functionality enables the system to compensate for hematocrit effects on glucose readings, improving measurement precision while maintaining a unified device structure rather than requiring separate instruments.
2Measurement precision
If hematocrit correction mechanisms are added to test strips, then measurement precision improves, but device complexity increases
Solution Approach 1:
The test strip incorporates spatially separated test zones: a first zone containing glucose oxidase for glucose measurement and a second zone containing hemoglobin-binding compounds for hematocrit measurement. This segmentation allows independent optimization of each measurement function while using a single integrated strip, improving glucose reading accuracy without excessive formulation complexity.
Solution Approach 2:
The system changes the measurement parameter from glucose concentration alone to a combination of glucose concentration and hematocrit level. By measuring hematocrit through hemoglobin binding in the second test zone and using this information to correct glucose readings, the system achieves higher measurement precision while adding only one additional chemical system to the strip formulation.
3Measurement precision
If multiple test zones are integrated in a single strip, then measurement precision improves through hematocrit compensation, but ease of operation deteriorates due to complex sample application
Solution Approach 1:
The patent merges glucose measurement and hematocrit measurement functions into a single integrated test strip with two test zones. A single blood sample application to the strip simultaneously fills both test zones, enabling both measurements without requiring separate sample applications or complex user操作流程, thus maintaining ease of operation while achieving improved measurement precision.
Solution Approach 2:
The test strip is designed as a universal platform that performs both glucose quantification and hematocrit determination using a single sample application. The multi-functional design allows the same sample to be analyzed for multiple parameters simultaneously, improving measurement precision through hematocrit compensation without adding operational steps for the user.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach provides accurate glucose measurements with a bias of less than ±10% across a wide hematocrit range, significantly improving the reliability of blood glucose monitoring by effectively accounting for hematocrit variations.
Implementation Method 1
measuring an output signal from the plurality of electrodes during the test sequence
Implementation Method 2
glucose is oxidized to gluconic acid by the oxidized form of glucose oxidase (GO (ox)). During the reaction, the oxidized enzyme GO (ox) is converted to its reduced state, which is denoted as GO (red). Next, the reduced enzyme GO (red) is re-oxidized back to GO (ox) by reaction with Fe(CN)6 3-
Data Source
Figure 1A
Figure 1B
Figure 2A
AI summary
Various embodiments that allow for detection of a fill sufficiency and a more accurate analyte concentration by determining at least one physical characteristic, particularly hematocrit, of the blood sample containing the analyte, particularly glucose, and deriving a specific sampling time based on a relationship between the physical characteristic, the estimated analyte concentration and sampling time. In this way the analyte concentration can be determined with greater accuracy at the specific sampling time point and fill sufficiency can be determined if the signal outputs of the working electrodes do not meet certain thresholds.