Droplets and Gravity: A Smart Way to Handle Tiny Liquids

The Challenge of Digital Microfluidics

In the realm of digital microfluidics, precise control of tiny liquid droplets is crucial. Traditional methods rely on electrowetting on dielectric (EWOD) to manipulate droplets, but their splitting capabilities are limited by electrode shapes.

A Clever Solution: Gravity-Induced Size-Tuning Splitting (GITS)

Scientists have introduced a groundbreaking approach—GITS—which leverages gravity to enhance droplet splitting. This method eliminates the need for specialized electrodes or complex setups.

Key Findings

• Experiments and simulations confirmed that gravity amplifies the EWOD force in a specific direction, aiding droplet formation.
• Droplet size can be fine-tuned based on:
• Droplet volume
• Applied voltage
• Contact line ratios between the droplet and electrodes
• Critical size for passive dropping varies with gap height, ensuring reliable behavior.

AI-Powered Precision

The GITS method was further enhanced with artificial intelligence (AI) to control contact lines and gravity-induced droplet dropping. This innovation achieved splitting ratios ranging from 1 to 7.33 with remarkable precision.

Biomedical Applications

The GITS method was successfully applied to handle reagents of varying sizes for cell viability assays, demonstrating its potential for flexible reagent configuration in future biomedical applications.