An Acoustofluidic Picoinjector

Area of Science:

• Microfluidics
• Acoustofluidics
• Biomedical Engineering

Background:

• Droplet microfluidics enables high-throughput assays in independent microenvironments.
• Picoinjection into droplets is crucial but faces challenges like high power needs, poor biocompatibility, and limited control.
• Existing picoinjection methods hinder the full potential of droplet microfluidic applications.

Purpose of the Study:

• To introduce a novel acoustofluidic picoinjector for precise, energy-efficient, and biocompatible reagent delivery into droplets.
• To overcome the limitations of current picoinjection techniques in droplet microfluidics.
• To demonstrate the platform's utility in chemical and biomedical research.

Main Methods:

• Utilizing acoustic pressure at the droplet interface for controlled picoinjection.
• Performing acid-base titrations by iterative picoliter reagent injection into droplets.
• Synthesizing metallic nanoparticles using the acoustofluidic picoinjector.

Main Results:

• Demonstrated on-demand, energy-efficient, and highly precise picoinjection.
• Successfully induced pH transitions in droplets via iterative reagent addition.
• Produced highly monodisperse and reproducible metallic nanoparticles, outperforming bulk methods.

Conclusions:

• The acoustofluidic picoinjector offers a precise, energy-efficient, and biocompatible solution for droplet microfluidics.
• This technology expands the capabilities of droplet microfluidics for diverse chemical and biological applications.
• Enables accurate reagent and sample delivery, broadening research possibilities.