Multilayered Membrane Retaining NAD(P) for Stable Sensor Sensitivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Implantable analyte sensors face challenges with short life spans and reduced sensitivity due to insufficient availability or diffusion of NAD(P) coenzymes, which are essential for the activity of enzymes like dehydrogenases.
Innovation Solution
The analyte sensor incorporates a multilayered membrane with a negatively charged polymer that overcoats the sensing layer containing an NAD(P)-dependent enzyme and a supply of NAD(P). This membrane limits the transport of NAD(P), maintaining a sufficient concentration within the sensing layer and enhancing sensor sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a multilayered membrane with negatively charged polymer is used to retain NAD(P) in the sensing layer, then sensor sensitivity is maintained over extended periods, but the device complexity increases
Solution Approach 1:
The membrane is divided into multiple layers with distinct functions: the negatively charged polymer layer specifically retains NAD(P) molecules through electrostatic interactions, while other layers provide structural support and analyte permeability. This segmentation allows each layer to be optimized for its specific purpose, resolving the contradiction between retention effectiveness and overall device complexity.
Solution Approach 2:
The membrane combines negatively charged polymer materials with other compatible materials to create a composite structure that achieves both NAD(P) retention and analyte permeability. The composite nature allows the membrane to simultaneously provide electrostatic retention of charged coenzymes while maintaining porosity for analyte diffusion, thus improving reliability without excessive complexity.
2Productivity
If the membrane is made highly permeable to allow analyte diffusion, then analyte detection efficiency improves, but NAD(P) may escape from the sensing layer reducing sensor performance
Solution Approach 1:
The membrane exhibits different properties at different scales: at the molecular level, the negatively charged polymer provides selective retention for NAD(P) molecules through electrostatic interactions, while at the macroscopic level, the membrane maintains high permeability for analyte diffusion. This local quality differentiation resolves the contradiction between retention and detection efficiency.
Solution Approach 2:
The negatively charged polymer acts as an intermediary that selectively interacts with NAD(P) molecules through electrostatic forces, allowing the membrane to retain coenzymes while simultaneously permitting analyte passage. This intermediary mechanism enables the membrane to mediate between the conflicting requirements of retention and permeability.
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 use of a multilayered membrane with negatively charged polymers effectively retains NAD(P) within the sensing layer, thereby maintaining sensor sensitivity over an extended period, such as 12 days, with minimal signal decay.
Implementation Method 1
the membrane comprises at least one layer of negatively charged polymer, and wherein the negatively charged polymer limits transport of the supply of NAD(P) from the sensing layer
Implementation Method 2
the multilayered membrane that overcoats at least a part of the sensing layer and is permeable to an analyte
Data Source
AI summary
The present disclosure provides analyte sensors comprising a sensing layer disposed upon a surface of a first working electrode, wherein the sensing layer comprises an NAD(P)-dependent enzyme and a supply of NAD(P); and a multilayered membrane that overcoats at least a part of the sensing layer and is permeable to an analyte, wherein the membrane comprises at least one layer of negatively charged polymer. The present disclosure also provides methods of using such analyte sensors for detecting one or more analytes preset in a biological sample and methods of manufacturing the analyte sensors.