Dry Slide Assay Reading Window Exclusion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Assays performed on dry slides face imprecision due to fluid stagnation variations caused by washing fluids, particularly at high analyte levels, leading to inaccuracies in light intensity measurements.
Innovation Solution
A method and apparatus that reduce the reading window to exclude interference areas caused by fluid stagnation, by determining and eliminating the stagnation area within the initial reading window, and positioning a reduced reading window, such as a crescent shape, to minimize the impact of washing fluid variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the reading window includes the entire fluid sample area, then the measurement covers all analyte regions, but the precision deteriorates due to inclusion of stagnation area variations from washing fluid
Solution Approach 1:
The reading window is segmented into multiple regions: a first region that excludes the stagnation area and a second region that includes the stagnation area. By selectively weighting or excluding signals from different regions, the patent achieves improved precision while maintaining comprehensive sample coverage.
Solution Approach 2:
Different regions within the reading window are assigned different quality weights. The first region (excluding stagnation area) is given higher weight for precision-critical measurements, while the second region (including stagnation area) is either excluded or given lower weight, creating local quality differentiation across the sample area.
2Measurement precision
If the reading window is reduced to exclude stagnation area, then the measurement precision improves, but the coverage of analyte regions decreases
Solution Approach 1:
The reading window is divided into a first region excluding the stagnation area and a second region including it. This segmentation allows the system to prioritize precision from the first region while still incorporating data from the second region, thereby maintaining broader analyte coverage without sacrificing measurement accuracy.
Solution Approach 2:
The patent applies partial action by selectively including or excluding specific regions based on their quality. Rather than completely excluding the stagnation area or including it fully, the system applies weighted inclusion, taking only the beneficial portion (first region) while minimizing the harmful portion (second region).
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 approach improves assay precision by selectively excluding light intensity variations from stagnation areas, resulting in more accurate and repeatable measurements, as demonstrated by improved Digoxin assay kinetics and precision across various samples and instruments.
Implementation Method 1
assays are performed by measuring the light intensity of an area of an image of a fluid sample
Data Source
AI summary
The present disclosure is directed to a method and apparatus for performing an assay on a dry slide or other solid media using a reduced reading window. In an embodiment, method of performing at least one assay comprises obtaining an image of a fluid sample located on a dry slide, positioning a reading window to correspond to an area of the fluid sample in the image, determining an interference area within the reading window based on light intensity, reducing the reading window to eliminate the interference area from the reading window, and performing at least one assay using the reduced reading window.