Passive microinjection within high-throughput microfluidics for controlled actuation of droplets and cells

Area of Science:

• Biotechnology
• Microfluidics
• Cellular Engineering

Background:

• Microinjection is crucial for precise delivery of molecules and cells.
• Existing microinjection methods are often slow and not suitable for high-throughput applications.
• There is a need for efficient and controlled microinjection techniques in droplet-based systems.

Purpose of the Study:

• To develop a new passive microinjection technique for high-throughput serial microinjection into droplets.
• To improve the speed, control, and efficiency of microinjection processes.
• To investigate the dynamics of multiphase flows and the impact of various parameters on microinjection efficacy.

Main Methods:

• A passive microinjection technique utilizing pressure-driven fluid flow and pulsative flow patterns.
• Integration into a high-throughput droplet microfluidic system with a microneedle injection station for droplet confinement.
• Three-dimensional (3D) computational fluid dynamics (CFD) analysis to model multiphase flow dynamics.
• Experimental validation of the developed microinjection model.

Main Results:

• Demonstrated rapid and highly controlled serial microinjection into droplets.
• Investigated the influence of pulsative flows, microneedle parameters, and synchronization on microinjection efficiency.
• Validated the computational model with experimental results, confirming the technique's feasibility.

Conclusions:

• The developed passive microinjection technique offers a significant advancement for high-throughput applications.
• This method enables precise and controlled delivery into droplets, overcoming limitations of existing techniques.
• Potential applications include tissue engineering, cell actuation, drug discovery, and novel drug delivery strategies.