Amperometric Sensor Insulating Substrate Electrode Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing amperometric electrochemical sensors face challenges such as complex manufacturing processes, limited lifetime due to membrane degradation, and the need for silicon substrates, which restricts miniaturization and flexibility in electrode design and substrate materials.

Innovation Solution

An amperometric electrochemical sensor with a simplified production method using an insulating substrate with patterned electrodes covered by a polymeric filtration membrane, allowing for nanostructured openings and direct electrode access, enabling use on non-silicon substrates like glass or ceramics, and featuring a dual-membrane configuration for enhanced adhesion and selectivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a diffusion membrane completely covers all three electrodes, then selectivity and protection are improved, but manufacturing complexity increases and electrode design flexibility is reduced

Engineering Contradiction:
ImproveselectivityVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The diffusion membrane is segmented to cover only the working electrode rather than all three electrodes. This is achieved by defining the membrane's active area through a mask during deposition, creating a localized selective barrier that simplifies manufacturing while maintaining measurement selectivity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The diffusion membrane's selective coverage is applied locally only where needed for measurement (working electrode) rather than uniformly across all electrodes. This local quality approach allows the counter and reference electrodes to remain exposed and accessible, simplifying electrical connections and manufacturing processes.

Inventive Principle:
Principle #3Local quality

2Manufacturing precision

If the working electrode is made large enough for membrane deposition, then membrane coverage is improved, but sensor miniaturization is hindered

Engineering Contradiction:
Improvemembrane coverageVSAvoidsensor size
Core Design Contradiction:
Manufacturing precisionVSVolume of moving object

Solution Approach 1:

The mask is applied beforehand during the membrane deposition process to define the precise area where the membrane should form. This preliminary action allows complete and uniform membrane coverage on the working electrode even when the electrode is small, enabling miniaturization while maintaining manufacturing precision.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The use of a mask during membrane deposition allows the membrane to be formed with controlled porosity and precise geometric definition. This approach enables adequate membrane coverage on miniaturized electrodes by controlling the deposition process rather than relying on electrode size.

Inventive Principle:
Principle #31Porous materials

3Adaptability or versatility

If an insulating layer with openings is used to define electrodes, then electrode shape flexibility is improved, but manufacturing process complexity increases

Engineering Contradiction:
Improveelectrode design flexibilityVSAvoidmanufacturing process complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

Instead of creating electrodes by removing material (openings in insulating layer), the invention inverts the approach by depositing the membrane through a mask that defines the electrode areas directly. This eliminates the need for complex insulating layer patterning and opening creation steps.

Inventive Principle:
Principle #13The other way round (Inversion)

Solution Approach 2:

The complex insulating layer with openings is extracted from the manufacturing process. The electrode definition function is achieved more simply through mask-guided membrane deposition, removing unnecessary manufacturing steps while maintaining electrode shape flexibility.

Inventive Principle:
Principle #2Taking out (Extraction)

4Adaptability or versatility

If electroreactive species are immobilized in the membrane, then measurement capability for non-electroactive species is improved, but membrane lifespan is reduced

Engineering Contradiction:
Improvemeasurement capabilityVSAvoidmembrane lifespan
Core Design Contradiction:
Adaptability or versatilityVSDuration of action of stationary object

Solution Approach 1:

Instead of immobilizing electroreactive species in the membrane, the invention uses the dissolved oxidoreducible substance itself as the intermediary that reacts at the working electrode surface. This eliminates membrane saturation and leakage issues while maintaining the ability to measure non-electroactive species through their interaction with the electrode.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The measurement system uses the target analyte (dissolved oxidoreducible substance) directly without requiring additional immobilized intermediaries. The substance serves its own measurement function by undergoing redox reactions at the electrode, eliminating the need for consumable membrane components and extending membrane lifespan.

Inventive Principle:
Principle #25Self-service

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 improves sensor adhesion, stability, and selectivity, enabling prolonged operation without recalibration, miniaturization, and compatibility with various substrates, while allowing direct measurement of oxidoreducible substances without the need for liquid electrolytes.

Implementation Method 1

The membrane defines a diffusion layer for the oxidoreducible substance

Methodology Applied
Scientific EffectDiffusion: Diffusion

Implementation Method 2

measuring the current flowing between the working electrode and the counter electrode, induced by a redox reaction at the working electrode

Methodology Applied
Scientific EffectRedox reactions: Redox Reactions

Data Source

PatentEP2419721B1Amperometric electrochemical sensor and method of manufacturing
Publication Date: 2019.04.10 NEROXIS
  • EP2419721B1 patent drawingFigure 1~2
  • EP2419721B1 patent drawingFigure 3~5
  • EP2419721B1 patent drawingFigure 4a~4h

AI summary

The present invention relates to an amperometric electrochemical sensor with a fixed potential used in a probe for measuring the content of an oxidation reduction substance dissolved in a liquid, in particular the chlorine content. The sensor (1) includes an insulating substrate (2), a set of electrodes consisting of a working electrode (3), an auxiliary electrode (4) and a reference electrode, at least one of said working electrode (3) and auxiliary electrode (4) being configured on said insulating substrate (2). At least one of said working electrode (3) and auxiliary electrode (4) is covered with an insulating layer (8), said insulating layer (8) including at least one opening exposing at least one of said working electrode (3) and auxiliary electrode (4).