Gas Microbubble Formation via Near-Infrared Femtosecond Laser Ablation in Live Cells.

Area of Science:

• Biophysics
• Cell Biology
• Laser Physics

Background:

• Intracellular molecule photodamage by near-infrared femtosecond lasers forms gas microbubbles.
• These microbubbles cause cell death and removal, offering potential for targeted ablation.

Purpose of the Study:

• Characterize laser-induced intracellular microbubbles using high-speed imaging.
• Develop a precise method for in vitro cellular motility studies.
• Evaluate the efficacy of chemical compounds in modulating cell motility.

Main Methods:

• High-speed imaging to analyze microbubble formation and dynamics.
• Single-pulse and repetitive (1 kHz) femtosecond laser irradiation.
• Creation of cell-free zones in cell monolayers for motility assays.
• Utilizing A549 lung cancer cells and the flavonoid apigenin.

Main Results:

• Intracellular microbubbles are larger than extracellular ones across various pulse energies.
• Lower energy threshold for intracellular microbubble formation allows precise cell ablation.
• Repetitive pulsing reduces threshold and increases bubble size, reaching saturation.
• Cell-free zone creation effectively enables in vitro motility studies.

Conclusions:

• Femtosecond laser-induced microbubbles provide a tool for precise intracellular ablation.
• The developed method accurately assesses cellular motility in vitro.
• Apigenin demonstrates dose-dependent inhibition of A549 cell motility, validating the screening potential.