Biosensor Capillary Segmentation for Hematocrit Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing biosensors face inaccuracies in measuring analyte concentrations due to hematocrit variations in blood samples, leading to incorrect glucose readings, which current correction methods either increase cost and complexity or prolong test time.
Innovation Solution
A biosensor system with separate capillaries for analyte concentration measurement and hematocrit determination, using impedance measurement between electrodes in a second capillary to calculate a correction factor for accurate glucose level determination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If hematocrit correction is implemented using prior art methods, then measurement precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent divides the biosensor into two separate capillaries: a first capillary for analyte concentration measurement and a second capillary for hematocrit determination. This segmentation allows each capillary to be optimized for its specific function, with the first capillary containing electrochemical sensors for analyte detection and the second capillary containing impedance measurement electrodes for hematocrit measurement, thereby improving overall measurement precision while maintaining manageable system complexity
Solution Approach 2:
The biosensor system performs multiple functions within a single device: it measures both analyte concentration (e.g., glucose) and hematocrit level using two separate capillaries. The first capillary executes electrochemical reactions for analyte detection, while the second capillary measures impedance to determine hematocrit. This multi-functionality enables comprehensive blood analysis without requiring separate devices, improving measurement accuracy through hematocrit correction
2Measurement precision
If hematocrit correction is implemented using prior art methods, then measurement precision is improved, but test time increases
Solution Approach 1:
The patent performs hematocrit determination and analyte concentration measurement simultaneously using two separate capillaries that both receive blood sample portions at the same time. The impedance measurement in the second capillary and the electrochemical reaction in the first capillary occur concurrently, allowing the correction factor to be calculated and applied without extending the overall test time, thus improving measurement precision without time penalty
Solution Approach 2:
The biosensor system maintains continuous useful action by simultaneously executing both the hematocrit measurement function in the second capillary and the analyte concentration measurement function in the first capillary. Both measurements proceed in parallel without interruption or sequential delay, ensuring that the correction process does not extend the test time while continuously improving measurement accuracy
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 and efficient correction for hematocrit-induced inaccuracies, reducing test time and complexity while maintaining cost-effectiveness.
Implementation Method 1
Electrochemical sensors comprise a reagent mixture containing at least an electron transfer agent (also referred to as an 'electron mediator') and an analyte specific bio-catalytic protein (e.g. a particular enzyme), and one or more electrodes. Such sensors rely on electron transfer between the electron mediator and the electrode surfaces and function by measuring electrochemical redox reactions.
Implementation Method 2
a second capillary disposed on the base layer configured to determine a value correlating to the hematocrit level of the blood sample, wherein the second capillary includes a second set of electrodes formed on the base layer
Data Source
Figure 1A~1B
Figure 1C
Figure 2A
AI summary
Methods and devices for determining the concentration of a constituent in a physiological sample are provided. The blood sample is introduced into a test strip with portions of the blood sample being directed to both a first capillary and a second capillary. The first capillary configured to electrochemically determine a concentration of a first analyte in a blood sample by measuring a signal across a set of electrodes. The second capillary is configured to determine a hematocrit value of the blood sample by measuring a signal across a second set of electrodes.