Lateral Flow Assay Device with Flow Bridging Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lateral flow assay devices face challenges in optimizing sample flow characteristics, leading to sample wastage, inadequate mixing of samples and reagents, and prolonged assay times, while the hydrophilic foil cover can hinder fluid flow and cause contamination.
Innovation Solution
A lateral flow device design featuring a substrate with projections for capillary flow, a hydrophilic foil or tape cover with a peripheral edge, and a flow bridging structure, such as a groove or bar, at the entrance of the absorbing zone to promote fluid flow and prevent wicking along the cover's edge, allowing for adjustable flow times and reduced sample volumes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a hydrophilic foil cover is placed over the absorbing zone to improve sample wicking, then the wicking performance is improved, but the cover can hinder fluid flow and cause contamination
Solution Approach 1:
The hydrophilic foil cover is segmented by introducing a peripheral edge that extends across the flow channel, dividing the cover into regions that serve different functions: one region maintains wicking performance while the other region allows controlled fluid flow, thus resolving the contradiction between wicking enhancement and flow hindrance
Solution Approach 2:
The peripheral edge of the hydrophilic foil cover acts as an intermediary structure between the absorbing zone and the flow channel. This edge structure mediates the interaction between the cover and fluid flow, allowing the cover to provide wicking support while preventing excessive flow hindrance and contamination risks
2Quantity of substance
If the flow channel is narrow to reduce sample volume, then sample volume is reduced, but flow stoppages and mixing inefficiency occur
Solution Approach 1:
The flow channel exhibits local quality variations with different sections having different width characteristics. The channel is narrow in the detection zone to reduce sample volume requirements, while broader sections are provided in flow transition zones to maintain flow continuity and mixing efficiency, thus resolving the contradiction between sample volume reduction and flow performance
3Device complexity
If the assay device uses conventional design without flow control features, then the device complexity is low, but sample wastage and prolonged assay times occur
Solution Approach 1:
The assay device incorporates preliminary flow control features including the peripheral edge structure and hydrophilic foil cover configuration that are designed in advance to optimize fluid flow characteristics. These features preliminarily control sample distribution and flow rate, preventing sample wastage and reducing assay time without requiring complex additional components
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 reduces sample wastage, enhances mixing and dissolution of detection materials, and improves assay precision by allowing smaller sample volumes with adjustable flow times, while minimizing flow stoppages and contamination risks.
Implementation Method 1
a plurality of projections extending from the substrate surface that are configured to enable capillary flow of an introduced fluid along the fluid flow path
Implementation Method 2
a hydrophilic foil or tape cover disposed over the absorbing zone, said cover having a peripheral edge extending across the entrance of the absorbing zone across a flow channel entering the absorbing zone
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
A lateral flow assay device includes a substrate having a top surface, as well as a sample receiving area disposed upon the top surface. At least one fluid flow path extends along the substrate from the sample receiving area, wherein the sample receiving area can be placed in contact with a peripheral reservoir formed at a sample addition area to draw sample therefrom in a controlled manner. The device can further include a reagent area that is designed to promote uniform dissolution of a deposited detection material by a sample moved through the device along the fluid flow path as well, as a flow channel configure to promote mixing of sample and reagent and an absorbing or wicking zone configured to affect various flow characteristics.