Optically induced electrothermal microfluidic tweezers in bio-relevant media

Area of Science:

• Biophysics
• Cell Biology
• Microfluidics

Background:

• Non-contact micro-manipulation techniques are crucial for studying fragile biological samples.
• Rapid electrokinetic patterning (REP) is an effective method for manipulating synthetic particles in low-salt solutions.
• Manipulating biological cells with REP is challenging due to their sensitivity to hypotonic media.

Purpose of the Study:

• To adapt Rapid electrokinetic patterning (REP) for manipulating biological cells in isotonic, bio-relevant media.
• To investigate challenges and solutions for REP in physiological conditions.
• To demonstrate REP's utility with mammalian cells in custom isotonic formulations.

Main Methods:

• Testing various salt- and sugar-based isotonic media formulations for REP compatibility.
• Utilizing dielectric passivation layers on device electrodes.
• Suspending murine pancreatic cancer cells in a sucrose-dextrose isotonic medium for manipulation.

Main Results:

• Successful REP manipulation of cells in low-concentration salt-based media (0.1x PBS) with passivated electrodes.
• Demonstrated REP manipulation of murine pancreatic cancer cells in a sugar-based isotonic medium.
• Established protocols for REP in bio-relevant isotonic electrolytes.

Conclusions:

• REP can be effectively adapted for manipulating biological cells in isotonic media, overcoming previous limitations.
• This technique opens new avenues for high-impact applications in cell biomechanics and 3D bioprinting.
• The study provides a foundation for using REP in diverse biological research settings.