Surfactant-Modified Droplet Loading into Nanowell Arrays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bead-based digital assays face challenges in efficiently loading droplets containing suspended beads into femtoliter-sized nanowell arrays, which is crucial for detecting low concentrations of protein biomarkers for early disease diagnosis and monitoring.
Innovation Solution
Incorporating a surfactant or detergent into the liquid droplets to reduce the contact angle with the nanowell array, facilitating more efficient loading by creating a hydrophilic surface and relieving trapped air, allowing for improved wetting and loading of droplets into the array.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If digital microfluidics is used to shuttle droplets of suspended beads into nanowell arrays, then droplet manipulation is achieved, but loading efficiency of single beads into femtoliter sized chambers remains poor
Solution Approach 1:
The patent changes the chemical composition parameter of the droplet by incorporating surfactants or detergents. This modifies the surface tension and wetting properties of the droplet, enabling it to efficiently load into the nanowell chambers. The surfactant concentration and type are optimized to achieve maximum loading efficiency while maintaining droplet integrity during manipulation.
Solution Approach 2:
The patent introduces surfactants as intermediary substances between the droplet and the nanowell array. These surfactants mediate the interaction by reducing interfacial tension and improving wetting, thereby facilitating the transfer of beads from the droplet into the nanowell chambers without direct mechanical contact that would cause loss.
2Productivity
If droplets are loaded into nanowell arrays without surfactant, then droplet integrity is maintained, but contact angle remains high and loading efficiency decreases
Solution Approach 1:
The patent modifies the surface chemical parameters of the droplet by adding surfactants. This changes the contact angle parameter from high (poor wetting) to low (good wetting), allowing the droplet to spread and load efficiently into the nanowell array. The surfactant concentration is carefully controlled to achieve optimal contact angle reduction.
Solution Approach 2:
The patent converts the harmful effect of high surface tension and poor wetting into a benefit by adding surfactants. The surfactants reduce surface tension, which initially might seem to compromise droplet integrity, but actually enables the droplet to wet the nanowell surface and load efficiently, transforming the wetting problem into a loading solution.
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 method enhances the loading efficiency of beads into nanowell arrays, enabling more effective detection and quantification of analytes at low concentrations, thereby improving diagnostic capabilities.
Implementation Method 1
each portion of the liquid droplet comprises a solid support and a detergent or surfactant
Implementation Method 2
the detergent or surfactant reduces the contact angle between the liquid droplet and the wells, and whereby a portion of the liquid droplet is loaded into each well of the array
Data Source
AI summary
Provided herein is a method of loading wells with a liquid droplet, or a portion thereof, wherein each liquid droplet comprises solid supports and a detergent or surfactant, such that the detergent or surfactant reduces the contact angle between the liquid droplet and the wells. Also provided is a method of detecting and quantifying an analyte of interest in a sample, which involves loading wells in an array with a liquid droplet according to aforementioned method, wherein the liquid droplet comprises an analyte captured on a solid support.