Emulsion Scanning via Phase Solidification for High Throughput Droplet Sorting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for sorting and detecting microdroplets in emulsions, used as chemical or biological microreactors, are inefficient due to high costs and limited throughput, particularly in applications like gene expression and diagnosis, where high flow rates are necessary for sensitivity and throughput.
Innovation Solution
A method involving a two-dimensional optical scan of emulsions with a solidified continuous phase to freeze drops in place, allowing for the construction of a two-dimensional image and subsequent localization, counting, and sampling of specific drops, using techniques such as thresholding and segmentation algorithms, and potentially crosslinking the continuous phase for solidification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If FACS or microfluidic techniques are used to sort drops one by one, then sorting capability is achieved, but throughput is limited to 1000-10000 drops per second
Solution Approach 1:
The invention transitions from one-dimensional sequential sorting (FACS/microfluidics processing drops in a single file) to two-dimensional parallel imaging (capturing multiple drops simultaneously in a plane). The camera-based system images a field of view containing many drops at once, enabling thousands of drops to be processed in parallel rather than sequentially, thereby dramatically increasing throughput while reducing device complexity.
Solution Approach 2:
The invention creates optical copies (images) of multiple drops simultaneously using a camera sensor, rather than physically manipulating each drop individually. The digital image captures fluorescent signals from numerous drops in parallel, allowing computational analysis to identify and sort target drops based on their fluorescent characteristics without requiring physical interaction with each drop.
2Productivity
If FACS equipment is used for sorting, then sorting capability is achieved, but cost increases to several hundred thousand euros
Solution Approach 1:
The invention replaces expensive, complex FACS equipment with a simpler, more affordable imaging system based on standard camera sensors and fluorescent microscopy. The system uses disposable or easily replaceable components such as fluorescently labeled droplets and standard optical filters, eliminating the need for costly specialized sorting hardware while maintaining high throughput capability.
Solution Approach 2:
The invention replaces the complex mechanical sorting mechanisms of FACS (electrostatic deflection, fluidic sorting channels) with an optical-digital system. A camera captures fluorescent images of drops, computational algorithms identify target drops based on fluorescence intensity, and sorting is achieved through simpler mechanical means such as magnetic actuation or microfluidic routing based on image analysis results.
3Speed
If drops are allowed to move during scanning, then scanning speed can be increased, but image quality and drop localization precision deteriorate
Solution Approach 1:
The invention changes the physical state parameter of the continuous phase from liquid to solid (or gel) to immobilize the droplets during imaging. This phase transition prevents drop movement while maintaining their spatial distribution, allowing high-resolution fluorescent imaging with precise localization. The solidified matrix preserves drop positions throughout the scanning process, enabling accurate measurement of fluorescent signals without motion blur or position drift.
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 enables faster and more efficient sorting and detection of microdroplets, significantly increasing throughput and reducing costs compared to existing microfluidics and FACS methods, while maintaining the ability to monitor chemical or biological reactions over time.
Implementation Method 1
by using a continuous phase which crosslinks when it is subjected to radiation, for example to ultraviolet radiation, and by subjecting this continuous phase to such radiation before scanning
Implementation Method 2
The partial images are preferably images of fluorescence signals emitted by the emulsion
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a method for reading an emulsion (3) comprising droplets and a continuous phase surrounding the droplets, said method comprising: - a two-dimensional scan of the emulsion (3), and - the construction of a two-dimensional image of the emulsion (3) from said scan. Preferably, the droplets do not move during the scan, for example by solidifying the continuous phase or by using a compact or semi-compact two-dimensional array of droplets. The method according to the invention may further include monitoring over time a chemical or biological reaction taking place in at least one of the droplets. The invention also relates to a device implementing this method. Application to the detection and/or sorting of microdroplets acting as microreactors or containing specific cells or molecules, in fields such as gene expression or diagnostics.