Multi-Objective Fluorescence Cell Sorting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current miniaturized fluorescence activated cell sorting (FACS) systems, or μFACS, face limitations in multiplexing capabilities, cost, and compatibility with traditional FACS protocols, particularly due to shared laser paths and the need for specialized coatings, which restrict their widespread adoption and functionality.
Innovation Solution
A μFACS system employing at least two excitation lasers with different orientations intersecting a fluidic channel within an interrogation region, coupled with a reduced number of detectors and compatible with planar microfluidic chips, allowing for simultaneous detection of multiple fluorescent markers and channels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a common path configuration is used for laser excitation light and flowing cells, then the system can be miniaturized, but the microfluidic geometry is limited and specialized coatings are required which increase cost and reduce compatibility
Solution Approach 1:
The patent separates the excitation light path from the collection light path by using multiple objectives positioned at different angles. Each objective independently illuminates or detects from a specific direction, eliminating the need for a shared optical path and specialized waveguiding coatings in the microfluidic channel.
Solution Approach 2:
The patent transitions from a single-axis common path configuration to a multi-dimensional arrangement where excitation and collection occur from different spatial angles through multiple objectives. This dimensional separation allows standard planar microfluidic chips to be used without specialized coatings.
2Device complexity
If a single excitation wavelength is used, then the system is simpler, but the number of fluorescent markers that can be identified is limited to about ten or fewer
Solution Approach 1:
The patent combines multiple excitation lasers with different wavelengths into a single illumination path through one objective. This merging approach allows simultaneous multi-color excitation without requiring separate optical paths for each wavelength, maintaining system compactness while enabling high multiplexing capability with unlimited fluorescent marker combinations.
Solution Approach 2:
The patent makes the single objective serve multiple functions by sequentially or simultaneously directing different wavelength lasers through it for excitation, while also collecting emission from multiple fluorescent markers. This multi-functional design eliminates the need for separate optical paths for each excitation wavelength.
3Measurement precision
If cuvettes are used with excitation lasers perpendicular to the collection path, then side scatter channels can be efficiently collected, but widely available planar microfluidic chips cannot be used and a large number of detectors are required
Solution Approach 1:
The patent segments the detection function across multiple objectives positioned at different angles, with each objective dedicated to collecting light from a specific direction (e.g., forward scatter, side scatter, fluorescence). This segmentation allows efficient collection of scattered light while using standard planar microfluidic chips instead of specialized cuvettes.
Solution Approach 2:
The patent introduces multiple objectives as intermediary optical elements between the sample and detectors. These objectives enable efficient light collection from different angles and facilitate the use of planar microfluidic chips by providing proper optical coupling without requiring specialized cuvette geometries.
4Adaptability or versatility
If a large number of detectors are used to achieve multiple channels, then the detection capability is enhanced, but the system becomes more complex and expensive
Solution Approach 1:
The patent combines multiple detection functions into fewer detectors by using spectral unmixing and spatial resolution techniques. Multiple objectives collect light from different angles or wavelengths, and advanced signal processing algorithms separate and identify individual fluorescent markers, reducing the total number of detectors needed while maintaining high multiplexing capability.
Solution Approach 2:
The patent replaces the mechanical approach of using separate physical detectors for each channel with an optical and computational approach. Multiple objectives capture light simultaneously, and software-based spectral unmixing algorithms differentiate between fluorescent markers, substituting complex mechanical detector arrays with a more integrated optical-system-plus-computation architecture.
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 configuration enhances multiplexing capabilities, reduces costs, and simplifies alignment while maintaining compatibility with traditional FACS protocols, enabling more compact and economical systems that can handle multiple fluorescent markers and channels, thus expanding the availability of miniaturized FACS systems.
Implementation Method 1
light from at least two excitation lasers have different orientations relative to the objective such that light from the at least two lasers passes through the objective and intersects a fluidic channel... light emitted from the plurality of fluorescently labeled particles
Data Source
AI summary
A system for fluorescence activated cell sorting includes at least two excitation lasers having different orientations relative to an objective such that light from the at least two lasers passes through the objective and intersects a fluidic channel at different positions within an interrogation region. The fluidic channel directs a flow of a plurality of fluorescently labeled particles through the interrogation region. The system further includes at least one detector and at least one optical element that directs light emitted from the plurality of fluorescently labeled particles and transmitted through the objective to the at least one detector. The system may further include optics for generating and detecting side and forward scattered light. Methods for operating example systems to collect fluorescent, side scattered and forward scattered light from a plurality of particles are also described herein.