Biosensor Reagent Layer Thickness Control for Reproducible Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing biosensors face challenges in achieving high reproducibility in biological substance measurements due to irregularities in reagent layer formation, particularly during the drying process, leading to inconsistencies in reagent concentration and amount.
Innovation Solution
A biosensor design with a reagent layer having a mean thickness of 5 μm to 10 μm and a thickness difference between peripheral and central parts ranging from -6 μm to +5 μm, formed by ejecting reagent liquid at predetermined pitches to create a dotted pattern and stacking droplets, ensuring uniform reagent dissolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If reagent liquid is applied by conventional methods (dipping, dispenser, screen printing, offset printing, ink-jet printing), then the reagent layer can be formed on the electrodes, but the reagent layer exhibits irregular thickness distribution (particularly during drying process) leading to poor measurement reproducibility
Solution Approach 1:
The patent applies parameter changes by controlling the ejection pitch of reagent liquid droplets and managing the drying process parameters. Specifically, the reagent liquid is ejected at pitches of 10 μm to 100 μm, and the drying is performed at temperatures of 20°C to 80°C to achieve a thickness difference between peripheral and central parts within -6 μm to +5 μm, thereby resolving the contradiction between manufacturing precision and measurement reproducibility.
Solution Approach 2:
The patent employs periodic action through a two-stage drying process. First, preliminary drying is performed to remove excess liquid, followed by final drying to achieve the desired thickness uniformity. This periodic drying approach prevents irregular thickness distribution that would otherwise occur in a single-stage drying process, thereby improving both manufacturing precision and measurement reproducibility.
2Ease of manufacture
If reagent liquid is applied by dipping method, then the reagent layer can be formed on the electrodes, but it is difficult to control the thickness and uniformity of the reagent layer
Solution Approach 1:
The patent replaces the mechanical dipping system with a non-contact ink-jet printing system. The ink-jet method ejects reagent liquid droplets onto the electrode surface without physical contact, allowing precise control of droplet placement and spacing. This substitution enables both ease of manufacture and precise thickness control, as the ejection pitch can be adjusted to achieve uniform thickness while simplifying the manufacturing process.
3Adaptability or versatility
If the reagent layer thickness is not controlled within specific ranges (mean thickness 5 μm to 10 μm, thickness difference -6 μm to +5 μm), then various application methods can be used, but lot-to-lot and within-lot differences increase reducing measurement accuracy
Solution Approach 1:
The patent applies parameter changes by establishing specific ranges for mean thickness (5 μm to 10 μm) and thickness difference (-6 μm to +5 μm). These parameter specifications ensure that measurements achieve high reproducibility with lot-to-lot and within-lot differences reduced to below 5%, while still allowing flexibility in the application method used to achieve these parameters.
Solution Approach 2:
The patent employs feedback by measuring the thickness of the reagent layer and adjusting the ejection pitch and drying conditions accordingly. This feedback mechanism ensures that the reagent layer consistently meets the specified thickness parameters, thereby maintaining high measurement precision while allowing adaptability in the application process.
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 design enhances reproducibility by reducing lot-to-lot and within-lot differences, providing accurate and consistent measurement results.
Implementation Method 1
ensuring uniform reagent dissolution
Data Source
AI summary
A biosensor that is capable of performing measurement with a high reproducibility is provided in one aspect.The present disclosure, as one aspect, relates to a biosensor that includes a base material, a conductive part including two or more electrodes provided on a surface of the base material, and a reagent layer provided on at least a part of the conductive part, the reagent layer has a mean thickness of 5 μm to 10 μm and a mean thickness difference, calculated based on the following formula, of −6 μm to +5 μm.[mean thickness difference]=[mean thickness of peripheral part]−[mean thickness of central part]