Microinjection in a microfluidic format using flexible and compliant channels and electroosmotic dosage control

Area of Science:

• Biotechnology
• Microfluidics
• Developmental Biology

Background:

• Microinjection is crucial for biological research, but current methods often lack precision and throughput.
• Existing systems can be complex, requiring multiple degrees of freedom for operation.
• High-throughput, precise microinjection is needed for large-scale studies, particularly in developmental biology.

Purpose of the Study:

• To develop a novel, scalable microfluidic microinjection system with precise electroosmotic dosage control.
• To simplify the microinjection mechanism and enable high-throughput processing.
• To demonstrate the system's efficacy and safety using Zebrafish embryos.

Main Methods:

• A polydimethylsiloxane (PDMS)-based microfluidic device with an integrated microneedle actuated by compliant channel deformation.
• Electroosmotic flow (EOF) for precise, non-pulsating reagent transport and electrical dosage control (5 V-25 V).
• Characterization of electrical properties and flow rates using Zebrafish embryos and model solutions; development of electrical feedback for dosing and needle positioning.

Main Results:

• Demonstrated a simplified, single-degree-of-freedom injection mechanism within an enclosed channel.
• Achieved precise individual dosing and needle positioning verification using electrical feedback.
• Preliminary viability studies showed normal development in Zebrafish embryos injected with ultrapure water at 48 hours.

Conclusions:

• The developed microfluidic microinjection system offers a scalable, high-throughput solution with precise electroosmotic control.
• The system simplifies existing methods and enhances accuracy through electrical feedback mechanisms.
• The device is suitable for biological applications, as evidenced by the successful viability study on Zebrafish embryos.