Automated Dielectrophoretic Tweezers-Based Force Spectroscopy System in a Microfluidic Device

Area of Science:

• Biophysics
• Nanotechnology
• Analytical Chemistry

Background:

• Investigating intermolecular weak binding interactions is crucial in various scientific fields.
• Existing methods for measuring these forces can be complex and costly.

Purpose of the Study:

• To develop and validate an automated dielectrophoretic (DEP) tweezers-based force spectroscopy system.
• To provide a simple, low-cost platform for examining intermolecular weak binding interactions.

Main Methods:

• The system integrates interdigitated electrodes, micro-sized polystyrene particles as DEP tweezers/probes, a microfluidic device, function generator, high voltage amplifier, microscopy with a high-speed CCD camera, and a LabVIEW-based computer control system.
• Automated force spectroscopy was performed using DEP tweezers to apply controlled forces.
• Measurement reliability was verified by quantifying known weak interactions, including hydrogen bonds and Van der Waals forces.

Main Results:

• The automated DEP tweezers system successfully measured intermolecular weak binding interactions.
• The system demonstrated reliability in quantifying forces such as hydrogen bonds and Van der Waals interactions.
• The linearity of force loading rates was observed and controllable by adjusting voltage increment steps.

Conclusions:

• The developed automated DEP tweezers system offers a simple and low-cost solution for investigating intermolecular weak binding interactions.
• This platform enhances the accessibility and efficiency of force spectroscopy for studying molecular interactions.