Polyurethane Membrane for Continuous Glucose Sensor Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrochemical sensors for monitoring glucose levels, particularly in diabetic patients, face challenges with accuracy and longevity due to noise interference and short-term or inaccurate readings, especially when implanted or transcutaneously.
Innovation Solution
A continuous analyte measurement device with a sensing mechanism and a membrane comprising polyurethane and a hydrophilic portion, which includes an enzyme to react with the analyte, providing a mean absolute relative difference of no more than 8% over a sensor session of at least 3 days, and a system with a processor and user interface to display accurate data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional membranes are used in electrochemical sensors, then the sensor can be manufactured with standard materials, but the sensor accuracy deteriorates due to noise interference from interfering species
Solution Approach 1:
The patent applies composite materials by combining polyurethane with hydrophilic polymers (such as polyethylene glycol, polyvinylpyrrolidone, or carboxymethyl cellulose) to create a membrane with dual functionality: the polyurethane provides structural integrity and selectivity, while the hydrophilic polymer reduces noise interference from interfering species through selective permeability and anti-fouling properties, thereby improving sensor accuracy
Solution Approach 2:
The patent utilizes porous materials by incorporating hydrophilic polymers that create selective pores and channels in the membrane structure. These pores allow selective transport of analyte molecules while blocking or reducing the passage of interfering species, thus minimizing noise interference and enhancing measurement precision
2Duration of action of moving object
If implantable or transcutaneous sensors are used for continuous monitoring, then continuous glucose detection is achieved, but the sensor reliability deteriorates due to short-term or inaccurate readings over extended periods
Solution Approach 1:
The composite membrane structure maintains stable performance over extended sensor sessions by combining the biocompatibility and structural stability of polyurethane with the anti-fouling and selective permeability of hydrophilic polymers, preventing protein adsorption and membrane degradation that would otherwise cause accuracy drift over time
Solution Approach 2:
The patent modifies membrane parameters by adjusting the composition ratio of polyurethane to hydrophilic polymer, controlling membrane thickness, and optimizing cross-linking density to achieve optimal balance between analyte permeability, interference rejection, and long-term stability, ensuring reliable readings throughout the sensor session
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
The solution ensures accurate and continuous glucose monitoring over extended periods with reduced noise interference, achieving a high level of accuracy and reliability in glucose level detection.
Implementation Method 1
the membrane comprises an enzyme configured to react with the analyte
Implementation Method 2
the membrane comprises a polyurethane and a hydrophilic portion
Data Source
AI summary
Devices and methods are described for providing continuous measurement of an analyte concentration. In some embodiments, the device has a sensing mechanism and a sensing membrane that includes at least one surface-active group-containing polymer and that is located over the sensing mechanism. The sensing membrane may have a bioprotective layer configured to substantially block the effect and/or influence of non-constant noise-causing species.