A Simple Microfluidic Chip for Long-Term Growth and Imaging of Caenorhabditis elegans
April 11th, 2022
2.3K views
The protocol describes a simple microfluidic chip design and microfabrication methodology used to grow C. elegans in presence of a continuous food supply for up to 36 h. The growth and imaging device also enables intermittent long-term high-resolution imaging of cellular and sub-cellular processes during development for several days.
Overview
This protocol outlines a microfluidic chip design and fabrication method for growing C. elegans with a continuous food supply for up to 36 hours. It also facilitates long-term high-resolution imaging of cellular processes during development.
Key Study Components
Area of Science
- Neuroscience
- Microfluidics
- Developmental Biology
Background
- The technique allows for the free growth of C. elegans within the device.
- High-resolution imaging can be performed while the animal is trapped.
- The device can be reused multiple times.
- Cleanliness is crucial during fabrication to prevent leakage.
Purpose of Study
- To develop a microfluidic device for studying C. elegans.
- To enable continuous food supply and imaging over extended periods.
- To facilitate the observation of cellular and sub-cellular processes.
Methods Used
- Designing flow and control layers using rectangular shapes in software.
- Printing photo masks with a laser plotter.
- Cutting silicon wafers into 2.5 cm squares.
- Cleaning wafers with potassium hydroxide and rinsing with deionized water.
Main Results
- The device successfully supports the growth of C. elegans.
- High-resolution imaging is achieved during development.
- The methodology allows for repeated use of the device.
- Maintaining cleanliness is essential for device functionality.
Conclusions
- This microfluidic chip design is effective for studying C. elegans.
- It provides a continuous food supply and enables long-term imaging.
- The approach can be adapted for various developmental studies.
Frequently Asked Questions
What is the main advantage of the microfluidic device?
The main advantage is that C. elegans can grow freely while being trapped for high-resolution imaging.
How long can C. elegans be grown in the device?
C. elegans can be grown for up to 36 hours with a continuous food supply.
What is the importance of cleanliness during fabrication?
Cleanliness is crucial to avoid dust and leakage during device operations.
Can the device be reused?
Yes, the device can be reused several times for experiments.
What materials are used in the fabrication of the device?
Silicon wafers and polyester-based films are used in the fabrication process.
What imaging capabilities does the device provide?
The device enables intermittent long-term high-resolution imaging of cellular processes.
Executive Industry Relevance
This microfluidic platform enables longitudinal imaging of C. elegans without anesthetic interference, supporting mechanistic de-risking in target validation and phenotypic screening workflows. By allowing repeated high-resolution imaging of the same animal over developmental timepoints, it improves predictive confidence in early discovery assays. The system provides a disease-relevant system for studying neuronal growth, vulval development, and dendritic arborization with translational biomarker alignment potential.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Scientific Value: Enables interrogation of therapeutic hypotheses through time-lapse imaging of neuronal process growth and subcellular events in individual animals.
- Operational Value: Supports biological de-risking by capturing temporal gene regulation patterns and developmental progression without confounding anesthetic effects.
Screening & Assay Development
- Scientific Value: Prepares validated biological systems for downstream workflows by maintaining animal health and enabling continuous food supply during extended culture.
- Operational Value: Enhances assay standardization and reproducibility through consistent immobilization via elastomeric membrane deflection using nitrogen gas pressure.
Translational & Preclinical Research
- Scientific Value: Provides disease-relevant system continuity from discovery through preclinical validation by imaging dendritic arborization in PVD sensory neurons across L2-L4 stages.
- Operational Value: Facilitates risk-adjusted advancement decisions by generating quantitative dependent variable measurements such as neuronal process length increase (10.4 μm/hour).
Pipeline & Workflow Integration
The method integrates into the discovery continuum from hypothesis testing through lead identification by enabling repeated imaging sessions that support mechanistic de-risking and predictive confidence in target validation.
- Discovery Biology: Supports hypothesis testing and pathway clarification by immobilizing animals for high-resolution imaging of cellular and subcellular events over time.
- Screening: Delivers assay readiness and quantitative outputs through time-lapse imaging of developmental phenomena such as vulval formation and neuronal branching.
- Analytics: Enables measurement of dependent variables like neuronal process length and subcellular localization to compare conditions and track progression.
- Translational Research: Connects to preclinical continuity by modeling developmental processes relevant to human neurodevelopment and disease.
- Enterprise Reuse: Functions as a reusable capability due to cleanable PDMS design and standard worm handling compatibility, reducing per-assay cost.
Operational & Enterprise Impact
- Scientific Value: Predictive confidence through longitudinal imaging, target validation via subcellular resolution, and reduction of mechanistic ambiguity in developmental pathways.
- Operational Value: Standardization, reproducibility, and scalability enabled by single-pressure-line operation and no external valves.
- Strategic Value: Better go/no-go decisions, capital efficiency through device reuse, and reduced late-stage biological risk by detecting developmental defects early.
- Portfolio Impact: Risk-adjusted prioritization based on quantitative imaging readouts and developmental trajectory alignment.
Implementation Considerations
- Requires expertise in microfluidic fabrication, photolithography, and PDMS bonding techniques.
- Needs access to spin coaters, UV illuminators, plasma cleaners, and nitrogen gas pressure control systems.
- Demands cross-team standardization of chip preparation, priming, and worm loading protocols for consistent results.
- Requires adaptation considerations when scaling to different worm strains or developmental stages due to channel geometry constraints.
- Practical limitations include the need for dust-free fabrication to prevent leakage and careful handling to maintain membrane integrity during repeated use.
Biopharma FAQs
Why does immobilization via nitrogen gas deflection matter for target validation?
Immobilization using deflected PDMS membranes enables high-resolution imaging without anesthetics, allowing repeated observation of the same animal over time to validate targets involved in developmental processes such as neuronal growth and vulval formation.
How does independent variable isolation fit the discovery pipeline?
The chip isolates genetic or environmental variables by maintaining animals in a controlled environment with continuous food supply, enabling researchers to attribute observed changes in neuronal process length or dendritic branching to specific interventions.
What quantitative dependent variable measurements enable predictive confidence?
Time-lapse imaging provides quantitative readouts such as total neuronal process length increasing at 10.4 micrometers per hour, which supports predictive modeling of developmental progression and compound effects.
Why do replication requirements matter for cross-functional collaboration?
Replication is supported by the device’s reusability and standardized fabrication, allowing multiple teams to generate consistent longitudinal imaging data for target validation and assay development workflows.
What statistical analysis capabilities are required before implementation?
Implementation requires basic time-series analysis to track changes in subcellular structures over intervals (e.g., every 8–10 hours) and compare growth rates or branching patterns across conditions or genotypes.
